added bootloader for IHU

git-svn-id: https://svn.spreadspace.org/mur.sat@807 7de4ea59-55d0-425e-a1af-a3118ea81d4c

11 files changed, 1574 insertions, 0 deletions

diff --git a/software/pic.bootloader/Makefile b/software/pic.bootloader/Makefile
new file mode 100644
index 0000000..fb91150
--- /dev/null
+++ b/software/pic.bootloader/Makefile
@@ -0,0 +1,31 @@
+##
+##  spreadspace pic utils
+##
+##
+##  Copyright (C) 2011 Christian Pointner <equinox@spreadspace.org>
+##
+##  This file is part of spreadspace pic utils.
+##
+##  spreadspace pic utils is free software: you can redistribute it and/or modify
+##  it under the terms of the GNU General Public License as published by
+##  the Free Software Foundation, either version 3 of the License, or
+##  any later version.
+##
+##  spreadspace pic utils is distributed in the hope that it will be useful,
+##  but WITHOUT ANY WARRANTY; without even the implied warranty of
+##  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+##  GNU General Public License for more details.
+##
+##  You should have received a copy of the GNU General Public License
+##  along with spreadspace pic utils. If not, see <http://www.gnu.org/licenses/>.
+##
+
+ifndef TARGET
+$(error You need to specify a target, call make with TARGET=xyz)
+endif
+
+all:
+	$(MAKE) -f Makefile-$(TARGET) $@
+
+%:
+	$(MAKE) -f Makefile-$(TARGET) $@
diff --git a/software/pic.bootloader/Makefile-IHU b/software/pic.bootloader/Makefile-IHU
new file mode 100644
index 0000000..4689f83
--- /dev/null
+++ b/software/pic.bootloader/Makefile-IHU
@@ -0,0 +1,26 @@
+##
+##  spreadspace pic utils
+##
+##
+##  Copyright (C) 2011 Christian Pointner <equinox@spreadspace.org>
+##
+##  This file is part of spreadspace pic utils.
+##
+##  spreadspace pic utils is free software: you can redistribute it and/or modify
+##  it under the terms of the GNU General Public License as published by
+##  the Free Software Foundation, either version 3 of the License, or
+##  any later version.
+##
+##  spreadspace pic utils is distributed in the hope that it will be useful,
+##  but WITHOUT ANY WARRANTY; without even the implied warranty of
+##  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+##  GNU General Public License for more details.
+##
+##  You should have received a copy of the GNU General Public License
+##  along with spreadspace pic utils. If not, see <http://www.gnu.org/licenses/>.
+##
+
+PROJECT := bootloader-IHU
+PROC_TYPE := 16F887
+
+include ../pic.include.mk
diff --git a/software/pic.bootloader/bootloader-IHU.asm b/software/pic.bootloader/bootloader-IHU.asm
new file mode 100644
index 0000000..bdf56f8
--- /dev/null
+++ b/software/pic.bootloader/bootloader-IHU.asm
@@ -0,0 +1,96 @@
+  ;;
+  ;;  spreadspace pic utils
+  ;;
+  ;;
+  ;;  Copyright (C) 2011 Christian Pointner <equinox@spreadspace.org>
+  ;;
+  ;;  This file is part of spreadspace pic utils.
+  ;;
+  ;;  spreadspace pic utils is free software: you can redistribute it and/or modify
+  ;;  it under the terms of the GNU General Public License as published by
+  ;;  the Free Software Foundation, either version 3 of the License, or
+  ;;  any later version.
+  ;;
+  ;;  spreadspace pic utils is distributed in the hope that it will be useful,
+  ;;  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  ;;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  ;;  GNU General Public License for more details.
+  ;;
+  ;;  You should have received a copy of the GNU General Public License
+  ;;  along with spreadspace pic utils. If not, see <http://www.gnu.org/licenses/>.
+  ;;
+  ;; -------------------------------------
+  ;; PREAMBLE
+
+  LIST      p=16F887
+  include   "p16f887.inc"
+  __config  _CONFIG1,  _DEBUG_OFF & _LVP_OFF & _FCMEN_OFF & _IESO_OFF & _BOR_NSLEEP & _CPD_OFF & _CP_OFF & _MCLRE_OFF & _PWRTE_ON & _WDT_OFF & _XT_OSC
+  __config  _CONFIG2,  _BOR21V & _WRT_256
+
+  ;; -------------------------------------
+  ;; DEFINES (chip/com specific)
+#define BOOTPIN           PORTA,4
+USERVECT        EQU       H'100'
+ISRVECT         EQU       USERVECT + H'4'
+FLASH_BOUNDARY  EQU       b'00001111' ; flash write boundary is at 16 bytes boundaries
+
+VERSION_MAJ     EQU       .0
+VERSION_MIN     EQU       .1
+NAME_0          EQU       'I'
+NAME_1          EQU       'H'
+NAME_2          EQU       'U'
+DEVID_L         EQU       H'82'
+DEVID_H         EQU       H'20'
+FLASH_SIZE_L    EQU       H'00'
+FLASH_SIZE_H    EQU       H'20'       ; 0x2000 -> 8192 Words of Flash
+FSS             EQU       .16         ; writing is done 8 words at a time but 16 words get erased
+EEPROM_SIZE_L   EQU       H'00'
+EEPROM_SIZE_H   EQU       H'01'       ; 0x0100 -> 256 Bytes of EEPROM
+MESS            EQU       .64         ; this limit is because of to combuff size and single byte len field for messages
+SUPPORTED_H     EQU       .0
+SUPPORTED_L     EQU       b'00000110' ; only read/write flash is supported by now
+
+#define HOOK_CMD_RESET    cmd_not_impl
+#define HOOK_CMD_R_FLASH  cmd_r_flash
+#define HOOK_CMD_W_FLASH  cmd_w_flash
+#define HOOK_CMD_R_EEPROM cmd_not_impl
+#define HOOK_CMD_W_EEPROM cmd_not_impl
+#define HOOK_CMD_R_CONFIG cmd_not_impl
+#define HOOK_CMD_W_CONFIG cmd_not_impl
+
+  ;; Variables
+combuff         EQU       H'0020'
+current_cmdlen  EQU       H'0070'
+csum            EQU       H'0071'
+flags           EQU       H'007D'
+cnt             EQU       H'007F'
+
+  ;; -------------------------------------
+  ;; DEFINES (defines)
+#include "generic-defines.inc"
+
+  ;; -------------------------------------
+  ;; Bootloader init
+#include "generic-init.inc"
+
+  ;; -------------------------------------
+  ;; Bootloader (com specific subroutines and init)
+#include "com-16f887-uart.inc"
+
+  ;; -------------------------------------
+  ;; Bootloader (generic init/body)
+#include "generic-mainloop.inc"
+
+  ;; -------------------------------------
+  ;;  chip specific commands
+#include "cmds-16f887.inc"
+
+  ;; -------------------------------------
+  ;; -------------------------------------
+  ;; dummy user code
+  org       USERVECT
+  goto      USERVECT
+
+  ;; -------------------------------------
+  ;; END
+  end
diff --git a/software/pic.bootloader/cmds-16f887.inc b/software/pic.bootloader/cmds-16f887.inc
new file mode 100644
index 0000000..144150e
--- /dev/null
+++ b/software/pic.bootloader/cmds-16f887.inc
@@ -0,0 +1,117 @@
+  ;;
+  ;;  spreadspace pic utils
+  ;;
+  ;;
+  ;;  Copyright (C) 2011 Christian Pointner <equinox@spreadspace.org>
+  ;;
+  ;;  This file is part of spreadspace pic utils.
+  ;;
+  ;;  spreadspace pic utils is free software: you can redistribute it and/or modify
+  ;;  it under the terms of the GNU General Public License as published by
+  ;;  the Free Software Foundation, either version 3 of the License, or
+  ;;  any later version.
+  ;;
+  ;;  spreadspace pic utils is distributed in the hope that it will be useful,
+  ;;  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  ;;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  ;;  GNU General Public License for more details.
+  ;;
+  ;;  You should have received a copy of the GNU General Public License
+  ;;  along with spreadspace pic utils. If not, see <http://www.gnu.org/licenses/>.
+  ;;
+
+  ;; flash read --------
+cmd_r_flash
+  movlw     FSS                 ; initialize EEADR:EEADRH and FSR
+  movwf     cnt
+  movlw     b'01011000'
+  movwf     STATUS
+  movlw     combuff + .2
+  movwf     FSR
+  movf      INDF,w
+  movwf     EEADR
+  incf      FSR,f
+  movf      INDF,w
+  movwf     EEADRH
+read_flash_segment_loop
+  bsf       STATUS,RP0          ; perform the actual read
+  bsf       EECON1,EEPGD
+  bsf       EECON1,RD
+  nop
+  nop
+  bcf       STATUS,RP0
+  movf      EEDAT,w             ; load code word from EEDAT:EEDATH to combuff
+  movwf     INDF
+  incf      FSR,f
+  movf      EEDATH,w
+  movwf     INDF
+  incf      FSR,f
+  incfsz    EEADR,f             ; increment flash address
+  goto      read_flash_segment_next
+  incf      EEADRH,f
+read_flash_segment_next
+  decfsz    cnt,f
+  goto      read_flash_segment_loop
+  bcf       STATUS,RP1
+  clrf      combuff + .2  ; = E_OK
+  movlw     .1 + .2*FSS   ; bytes to send
+  call      send_answer
+  goto      wait_new_cmd
+
+  ;; flash write --------
+cmd_w_flash
+  movf      combuff + .3,f      ; if addr[15:8] == 0 -> boot loader section
+  btfsc     STATUS,Z
+  goto      address_prohibited
+  movlw     FLASH_BOUNDARY      ; addr on boundary?
+  andwf     combuff + .2,w
+  btfss     STATUS,Z
+  goto      address_invalid
+  movlw     FSS                 ; initialize EEADR:EEADRH and FSR
+  movwf     cnt
+  movlw     b'01011000'
+  movwf     STATUS
+  movlw     combuff + .2
+  movwf     FSR
+  movf      INDF,w
+  movwf     EEADR
+  incf      FSR,f
+  movf      INDF,w
+  movwf     EEADRH
+
+write_flash_segment_loop
+  incf      FSR,f               ; load code word into EEDAT:EEDATH
+  movf      INDF,w
+  movwf     EEDAT
+  incf      FSR,f
+  movf      INDF,w
+  movwf     EEDATH
+
+  bsf       STATUS,RP0          ; now start the acutal write sequence
+  bsf       EECON1,EEPGD
+  bsf       EECON1,WREN
+  movlw     H'55'
+  movwf     EECON2
+  movlw     H'AA'
+  movwf     EECON2
+  bsf       EECON1,WR
+  nop
+  nop
+  bcf       EECON1,WREN
+  bcf       STATUS,RP0
+  incfsz    EEADR,f             ; increment flash address
+  goto      write_flash_segment_next
+  incf      EEADRH,f
+write_flash_segment_next
+  decfsz    cnt,f
+  goto      write_flash_segment_loop
+  bsf       STATUS,RP0
+  clrw                          ; check if a write error occured
+  btfsc     EECON1,WRERR
+  movlw     E_FLASH_WERR
+  bcf       STATUS,RP1
+  bcf       STATUS,RP0
+  movwf     combuff + .2  ; = E_OK
+  movlw     .1            ; bytes to send
+  call      send_answer
+  goto      wait_new_cmd
diff --git a/software/pic.bootloader/com-16f887-uart.inc b/software/pic.bootloader/com-16f887-uart.inc
new file mode 100644
index 0000000..b2b6812
--- /dev/null
+++ b/software/pic.bootloader/com-16f887-uart.inc
@@ -0,0 +1,75 @@
+  ;;
+  ;;  spreadspace pic utils
+  ;;
+  ;;
+  ;;  Copyright (C) 2011 Christian Pointner <equinox@spreadspace.org>
+  ;;
+  ;;  This file is part of spreadspace pic utils.
+  ;;
+  ;;  spreadspace pic utils is free software: you can redistribute it and/or modify
+  ;;  it under the terms of the GNU General Public License as published by
+  ;;  the Free Software Foundation, either version 3 of the License, or
+  ;;  any later version.
+  ;;
+  ;;  spreadspace pic utils is distributed in the hope that it will be useful,
+  ;;  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  ;;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  ;;  GNU General Public License for more details.
+  ;;
+  ;;  You should have received a copy of the GNU General Public License
+  ;;  along with spreadspace pic utils. If not, see <http://www.gnu.org/licenses/>.
+  ;;
+
+  ;; --- transmit byte and add it to csum
+com_tx_byte
+  btfss     PIR1,TXIF
+  goto      com_tx_byte
+  movwf     TXREG
+  xorwf     csum,f
+  return
+
+  ;; ---- wait for byte to be received
+com_rx_byte
+  btfsc     RCSTA,OERR
+  goto      uart_rx_oe
+  btfss     PIR1,RCIF
+  goto      com_rx_byte
+  btfsc     RCSTA,FERR
+  goto      uart_rx_fe
+  movf      RCREG,w
+  return
+
+uart_rx_oe                ; recover from overflow
+  bcf       RCSTA,CREN
+  bsf       RCSTA,CREN
+  goto      com_rx_byte
+
+uart_rx_fe                ; recover from framing error
+  movf      RCREG,w
+  goto      com_rx_byte
+
+  ;; ----- initialize com (not a subroutine, com_init is called by generic_init
+com_init
+  ;; bank 3
+  bsf       STATUS,RP0
+  bsf       STATUS,RP1
+  ;;movlw     b'00001000'   ; TX non-inverted, 16bit Baudrate, no auto baud detect
+  movlw     b'00011000'   ; TX inverted, 16bit Baudrate, no auto baud detect
+  movwf     BAUDCTL
+
+  ;; bank 1
+  bcf       STATUS,RP1
+  movlw     b'01110000'   ; set internal OSC to 8MHz
+  movwf     OSCCON
+  movlw     b'00100100'   ; Baudrate = High Speed, async mode, transmit enabled, 8bit
+  movwf     TXSTA
+  movlw     .34           ; Baudrate = 57600 (@ 8MHz) -> -0,79 % Error
+  ;; movlw     .51           ; Baudrate = 38400 (@ 8MHz) -> -0,002 % Error
+  ;; movlw     .103          ; Baudrate = 19200 (@ 8MHz) ->  0,16 % Error
+  movwf     SPBRG
+  clrf      SPBRGH
+
+  ;; bank 0
+  bcf       STATUS,RP0
+  movlw     b'10010000'   ; enable Serial Port, 8bit, enable continues receive, disable address detection
+  movwf     RCSTA
diff --git a/software/pic.bootloader/downloader.py b/software/pic.bootloader/downloader.py
new file mode 100755
index 0000000..27b15c3
--- /dev/null
+++ b/software/pic.bootloader/downloader.py
@@ -0,0 +1,339 @@
+#!/usr/bin/python
+#
+#  spreadspace pic utils
+#
+#
+#  Copyright (C) 2011 Christian Pointner <equinox@spreadspace.org>
+#
+#  This file is part of spreadspace pic utils.
+#
+#  spreadspace pic utils is free software: you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation, either version 3 of the License, or
+#  any later version.
+#
+#  spreadspace pic utils is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with spreadspace pic utils. If not, see <http://www.gnu.org/licenses/>.
+#
+
+'''spreadspace simple pic downloader.'''
+
+VERSION_MAJ = 0
+VERSION_MIN = 1
+
+### HEX File Magic
+
+def load_hex(file):
+    from ihexpic import IHexPic
+
+    fin = file
+    if fin == '-':
+        fin = sys.stdin
+    elif not os.path.isfile(fin):
+        print >> sys.stderr, "ERROR: File not found: %s" % fin
+        sys.exit(1)
+
+    hexdata = IHexPic()
+    hexdata.load_from_file(fin)
+    return hexdata
+
+def write_hex(file, codedata):
+    from ihexpic import IHexPic
+
+    fout = file
+    if fout == '-':
+        fout = sys.stdout
+
+    hexdata = IHexPic()
+    hexdata.load_from_dict(codedata)
+    hexdata.write_to_file(fout)
+
+def get_lowest_flash_addr(hexdata, fss):
+    lowest_code_addr = hexdata.get_lowest_addr()
+    return lowest_code_addr - (lowest_code_addr%fss)
+
+def get_highest_flash_addr(hexdata, fss):
+    highest_code_addr = hexdata.get_highest_addr()
+    return highest_code_addr + (fss - highest_code_addr%fss)
+
+def create_flash_image(hexdata, fss, sa, ea):
+    img = ( sa, [0xFFFF]*(ea-sa) )
+    for a,d in hexdata.items():
+        if a < ea:
+            img[1][a-sa] = d
+    return img
+
+def create_flash_segments(hexdata, fs, fss):
+    sa = get_lowest_flash_addr(hexdata, fss)
+    ea = get_highest_flash_addr(hexdata, fss)
+    if ea >= fs:
+        print >> sys.stderr, "WARNING: the hex file contains data after end of flash, these words will be ignored"
+        ea = fs
+
+    img = create_flash_image(hexdata, fss, sa, ea)
+    for i in xrange(0, ea, fss):
+        slice = tuple(img[1][i:i+fss])
+        if not all( (elem == 0xFFFF) for elem in slice):
+            yield (i + img[0], slice)
+
+
+### Interface to Bootloader
+
+def open_serial(device, baud):
+    import os
+    import tty
+    import termios
+    import serial
+
+    print >> sys.stderr,  "opening %s (%s Baud)" % (device, baud)
+
+    try:
+        dev = serial.Serial(port=device, baudrate=baud, timeout=3)
+        dev.flushInput()
+        dev.flushOutput()
+        return dev
+
+    except (ValueError, serial.SerialException), msg:
+        print >> sys.stderr, "ERROR: opening serial device: %s" % msg
+        sys.exit(3)
+
+def calc_csum(str):
+    cs = 0
+    for c in str:
+        cs ^= c
+    return cs
+
+def exec_command(dev, cmd, param, answer):
+    import struct
+
+    return_codes = { 0: "OK", 1: "invalid command", 2: "bad checksum",
+                     3: "not implemented", 4: "flash write error",
+                     5: "address invalid", 6: "address prohibited",
+                     7: "value out of bounds" }
+
+    dev.flushInput()
+    dev.flushOutput()
+
+    cstr = bytearray(struct.pack('<BB', cmd, len(param)+3) + param)
+    cstr.extend(struct.pack("<B", calc_csum(cstr)))
+    dev.write(cstr)
+
+    astr = bytearray()
+    astr += dev.read(4)
+    if len(astr) < 4:
+        print >> sys.stderr, "ERROR: timeout while reading response header (expected %d bytes, got %d)" % (4, len(astr))
+        sys.exit(4)
+
+    if astr[0] != cstr[0]:
+        print >> sys.stderr, "ERROR: bootloader returned wrong command code"
+        sys.exit(4)
+
+    ret = astr[2]
+    if ret != 0:
+        rstr = "invalid return code"
+        try:
+            rstr = return_codes[ret]
+        except KeyError:
+            pass
+        print >> sys.stderr, "ERROR: bootloader returned %d: %s" % (ret, rstr)
+        sys.exit(4)
+
+    answer_len = astr[1] - 4
+    if answer_len < struct.calcsize(answer):
+        print >> sys.stderr, "ERROR: short answer %d bytes received: expected %s bytes" % (answer_len, struct.calcsize(answer))
+        sys.exit(4)
+
+    if answer_len > 0:
+        tmp = bytearray()
+        tmp += dev.read(answer_len)
+        if len(tmp) < answer_len:
+            print >> sys.stderr, "ERROR: timeout while reading response (expected %d bytes, got %d)" % (answer_len, len(tmp))
+            sys.exit(4)
+
+        astr += tmp
+
+    if 0 != calc_csum(astr):
+        print >> sys.stderr, "ERROR: checksum error"
+        sys.exit(4)
+
+    return struct.unpack_from(answer, astr, 3)
+
+### low level commands
+
+def cmd_identify(dev, name):
+    data = exec_command(dev, 1, '', '<BB3sHHBHBH')
+    id = { 'ver_min': data[0], 'ver_maj': data[1], 'name': data[2], 'devid': data[3],
+           'fs': data[4], 'fss': data[5], 'es': data[6], 'mess': data[7], 'supported': data[8] }
+
+    if id['ver_maj'] != VERSION_MAJ:
+        print >> sys.stderr, "incompatible protocol version, expected: %d, got: %d" % (VERSION_MAJ, id['ver_maj'])
+        sys.exit(4)
+    if name and id['name'] != name:
+        print >> sys.stderr, "ERROR: the bootloaders name '%s' differs from the one supplied via" % id['name']
+        print >> sys.stderr, "       command line option '%s'. Are sure you are connected to the" % name
+        print >> sys.stderr, "       right device?"
+        sys.exit(4)
+
+    print >> sys.stderr, "connected with Bootloader '%s' Version %d.%d, (ID=%04X, %d words Flash, FSS=%d, %d bytes EEPROM, MESS=%d)" % \
+        (id['name'], id['ver_maj'], id['ver_min'], id['devid'], id['fs'], id['fss'], id['es'], id['mess'])
+    return id
+
+def cmd_boot(dev):
+    exec_command(dev, 2, '', '<')
+
+def cmd_reset(dev, id):
+    exec_command(dev, 3, '', '<')
+
+def cmd_read_flash_segment(dev, id, addr):
+    param = struct.pack('<H', addr)
+    return exec_command(dev, 4, param, '<%dH' % id['fss'])
+
+def cmd_write_flash_segment(dev, id, addr, data):
+    param = struct.pack('<H%dH' % id['fss'], addr, *data)
+    return exec_command(dev, 5, param, '<')
+
+def cmd_read_eeprom(dev, id, addr, len):
+    param = struct.pack('<HB', addr, len)
+    return exec_command(dev, 6, param, '<%dB' % len)
+
+def cmd_write_eeprom(dev, id, addr, data):
+    param = struct.pack('<HB%dB' % len(data), addr, len(data), *data)
+    return exec_command(dev, 7, param, '<')
+
+def cmd_read_config(dev, id, nr):
+    param = struct.pack('<B', nr)
+    data = exec_command(dev, 8, param, '<H')
+    return data[0]
+
+def cmd_write_config(dev, id, nr, word):
+    param = struct.pack('<BH', nr, word)
+    return exec_command(dev, 9, param, '<')
+
+
+### commands
+def boot(dev, id, file):
+    cmd_boot(dev)
+
+def write_flash(dev, id, file):
+    hexdata = load_hex(file)
+    for segment in create_flash_segments(hexdata, id['fs'], id['fss']):
+#        print >> sys.stderr, "%05X: %s" % (segment[0], ''.join('%04X '%i for i in segment[1]))
+        cmd_write_flash_segment(dev, id, segment[0], segment[1])
+
+def read_flash(dev, id, file):
+    codedata = {}
+    for addr in xrange(0, id['fs'], id['fss']):
+        data = cmd_read_flash_segment(dev, id, addr)
+#        print >> sys.stderr, "%05X: %s" % (addr, ''.join('%04X '%i for i in data))
+        a = addr
+        for d in data:
+            if d != 0x3FFF:
+                codedata[a] = d
+            a += 1
+    write_hex(file, codedata)
+
+def verify_flash(dev, id, file):
+    hexdata = load_hex(file)
+    err = 0
+    for segment in create_flash_segments(hexdata, id['fs'], id['fss']):
+        flashdata = cmd_read_flash_segment(dev, id, segment[0])
+        for file,flash in zip(segment[1] , flashdata):
+            if flash == 0x3FFF:
+                flash = 0xFFFF
+            if flash != file:
+                err = 1
+                break
+
+        if err !=0:
+            break
+
+    if err != 0:
+        print >> sys.stderr, "ERROR: verify failed!"
+        sys.exit(-1)
+    else:
+        print >> sys.stderr, "verify ok!"
+        sys.exit(0)
+
+commands = {
+    'boot': boot,
+    'write': write_flash,
+    'read': read_flash,
+    'verify': verify_flash
+}
+
+### Main
+
+if __name__ == '__main__':
+    import getopt
+    import sys
+    import os
+    import struct
+
+    usage = '''spreadspace simple pic downloader.
+Usage:
+    python downloader.py [options] INFILE
+
+Arguments:
+    INFILE      name of hex file for downloading.
+                Use '-' for reading from stdin.
+
+Options:
+    -h, --help              this help message.
+    -v, --version           version info.
+    --cmd=N                 the command to execute, one out of: "boot,read,write,verify"
+    --device=N              the serial port to use (default: /dev/ttyUSB0).
+    --baud=N                baudrate to use (default: 57600).
+    --name=N                the expected name of the bootloader.
+'''
+
+    device = "/dev/ttyUSB0"
+    baudrate = 57600
+    name = None
+    cmd = None
+
+    try:
+        opts, args = getopt.getopt(sys.argv[1:], "hv",
+                                  ["help", "version", "cmd=", "device=", "baud=", "name="])
+
+        for o, a in opts:
+            if o in ("-h", "--help"):
+                print >> sys.stderr, usage
+                sys.exit(0)
+            elif o in ("-v", "--version"):
+                print >> sys.stderr, "Version %d.%d" % (VERSION_MAJ, VERSION_MIN)
+                sys.exit(0)
+            elif o in ("--cmd"):
+                cmd = a
+            elif o in ("--device"):
+                device = a
+            elif o in ("--baud"):
+                baudrate = a
+            elif o in ("--name"):
+                name = a
+
+        if not args:
+            raise getopt.GetoptError('Hex file is not specified')
+
+        if len(args) > 1:
+            raise getopt.GetoptError('Too many arguments')
+
+        if not cmd:
+            raise getopt.GetoptError('You have to supply a command (boot,read,write,verify)')
+
+    except getopt.GetoptError, msg:
+        print >> sys.stderr, "ERROR: %s" % msg
+        print >> sys.stderr, usage
+        sys.exit(2)
+
+    dev = open_serial(device, baudrate)
+    id = cmd_identify(dev, name)
+
+    try:
+        commands[cmd](dev, id, args[0])
+    except KeyError:
+        print >> sys.stderr, "ERROR: unkown command '%s'" % cmd
diff --git a/software/pic.bootloader/generic-defines.inc b/software/pic.bootloader/generic-defines.inc
new file mode 100644
index 0000000..54ca01b
--- /dev/null
+++ b/software/pic.bootloader/generic-defines.inc
@@ -0,0 +1,50 @@
+  ;;
+  ;;  spreadspace pic utils
+  ;;
+  ;;
+  ;;  Copyright (C) 2011 Christian Pointner <equinox@spreadspace.org>
+  ;;
+  ;;  This file is part of spreadspace pic utils.
+  ;;
+  ;;  spreadspace pic utils is free software: you can redistribute it and/or modify
+  ;;  it under the terms of the GNU General Public License as published by
+  ;;  the Free Software Foundation, either version 3 of the License, or
+  ;;  any later version.
+  ;;
+  ;;  spreadspace pic utils is distributed in the hope that it will be useful,
+  ;;  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  ;;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  ;;  GNU General Public License for more details.
+  ;;
+  ;;  You should have received a copy of the GNU General Public License
+  ;;  along with spreadspace pic utils. If not, see <http://www.gnu.org/licenses/>.
+  ;;
+
+  ;; ERROR codes
+E_OK            EQU       .0
+E_INV_CMD       EQU       .1
+E_BAD_CSUM      EQU       .2
+E_NOT_IMPL      EQU       .3
+E_FLASH_WERR    EQU       .4
+E_ADDR_INVALID  EQU       .5
+E_ADDR_PROHIB   EQU       .6
+E_VALUE_OOB     EQU       .7
+
+  ;; CMD codes
+CMD_INVALID     EQU       .0
+
+CMD_IDENTIFY    EQU       .1
+CMD_BOOT        EQU       .2
+CMD_RESET       EQU       .3
+CMD_R_FLASH     EQU       .4
+CMD_W_FLASH     EQU       .5
+CMD_R_EEPROM    EQU       .6
+CMD_W_EEPROM    EQU       .7
+CMD_R_CONFIG    EQU       .8
+CMD_W_CONFIG    EQU       .9
+
+CMD_MAX         EQU       .9
+CMD_MIN_LEN     EQU       .3
+
+  ;; Flags
+#define F_CMD_STARTED     flags,0
diff --git a/software/pic.bootloader/generic-init.inc b/software/pic.bootloader/generic-init.inc
new file mode 100644
index 0000000..4c51fa9
--- /dev/null
+++ b/software/pic.bootloader/generic-init.inc
@@ -0,0 +1,61 @@
+  ;;
+  ;;  spreadspace pic utils
+  ;;
+  ;;
+  ;;  Copyright (C) 2011 Christian Pointner <equinox@spreadspace.org>
+  ;;
+  ;;  This file is part of spreadspace pic utils.
+  ;;
+  ;;  spreadspace pic utils is free software: you can redistribute it and/or modify
+  ;;  it under the terms of the GNU General Public License as published by
+  ;;  the Free Software Foundation, either version 3 of the License, or
+  ;;  any later version.
+  ;;
+  ;;  spreadspace pic utils is distributed in the hope that it will be useful,
+  ;;  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  ;;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  ;;  GNU General Public License for more details.
+  ;;
+  ;;  You should have received a copy of the GNU General Public License
+  ;;  along with spreadspace pic utils. If not, see <http://www.gnu.org/licenses/>.
+  ;;
+
+  org       .0
+  btfsc     BOOTPIN
+  goto      USERVECT
+  goto      com_init
+
+  ;; -------------------------------------
+  ;; goto user ISR
+  org       .4
+isr
+  goto      ISRVECT
+
+  ;; -------------------------------------
+  ;; Bootloader (Generic Subroutines)
+send_answer                     ; generic answer message, leave len of data in W
+  addlw     .3
+  movwf     combuff + .1
+  decf      combuff + .1,w
+  movwf     cnt
+  movlw     combuff
+  movwf     FSR
+  clrf      csum
+send_answer_next
+  movf      INDF,w
+  call      com_tx_byte
+  incf      FSR,f
+  decfsz    cnt,f
+  goto      send_answer_next
+
+  movf      csum,w
+  call      com_tx_byte
+  return
+
+  ;; ------------------
+ack_cmd                         ; short answers which only contain return code
+  movwf     combuff + .2
+  movlw     .1
+  call      send_answer
+  return
+
diff --git a/software/pic.bootloader/generic-mainloop.inc b/software/pic.bootloader/generic-mainloop.inc
new file mode 100644
index 0000000..1e93648
--- /dev/null
+++ b/software/pic.bootloader/generic-mainloop.inc
@@ -0,0 +1,174 @@
+  ;;
+  ;;  spreadspace pic utils
+  ;;
+  ;;
+  ;;  Copyright (C) 2011 Christian Pointner <equinox@spreadspace.org>
+  ;;
+  ;;  This file is part of spreadspace pic utils.
+  ;;
+  ;;  spreadspace pic utils is free software: you can redistribute it and/or modify
+  ;;  it under the terms of the GNU General Public License as published by
+  ;;  the Free Software Foundation, either version 3 of the License, or
+  ;;  any later version.
+  ;;
+  ;;  spreadspace pic utils is distributed in the hope that it will be useful,
+  ;;  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  ;;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  ;;  GNU General Public License for more details.
+  ;;
+  ;;  You should have received a copy of the GNU General Public License
+  ;;  along with spreadspace pic utils. If not, see <http://www.gnu.org/licenses/>.
+  ;;
+
+wait_new_cmd
+  movlw     combuff
+  movwf     FSR
+  clrf      combuff
+  clrf      current_cmdlen
+  clrf      flags
+
+wait_cmd
+  call      com_rx_byte
+  movwf     INDF          ; process received byte
+  incf      FSR,f
+  btfss     F_CMD_STARTED
+  goto      wait_cmd_len
+  movf      current_cmdlen,f
+  btfsc     STATUS,Z
+  goto      new_cmd
+  decfsz    current_cmdlen,f
+  goto      wait_cmd
+  goto      exec_cmd
+
+wait_cmd_len              ; command code received, now wait for length
+  bsf       F_CMD_STARTED
+  goto      wait_cmd
+
+new_cmd                   ; got new command code and length -> check it
+  movf      combuff,w
+  sublw     CMD_MAX
+  btfss     STATUS,C
+  goto      invalid_cmd
+  movlw     CMD_MIN_LEN         ; check for minimum command len
+  subwf     combuff + .1,w
+  btfss     STATUS,C
+  goto      invalid_cmd
+  movlw     .2                  ; 2 bytes already received
+  subwf     combuff + .1,w
+  movwf     current_cmdlen
+  goto      wait_cmd
+
+exec_cmd                        ; command is complete -> check csum
+  movlw     combuff
+  movwf     FSR
+  movf      combuff + .1,w
+  movwf     cnt
+  clrf      csum
+exec_cmd_check_csum
+  movf      INDF,w
+  xorwf     csum,f
+  incf      FSR,f
+  decfsz    cnt,f
+  goto      exec_cmd_check_csum
+  movf      csum,f
+  btfss     STATUS,Z
+  goto      csum_error
+
+  movf      combuff,w           ; command is correct and complete -> dispatch
+  addwf     PCL,f
+  goto      wait_new_cmd
+  goto      cmd_identify        ; identify
+  goto      cmd_boot            ; boot
+  goto      HOOK_CMD_RESET      ; reset
+  goto      HOOK_CMD_R_FLASH    ; read flash segment
+  goto      HOOK_CMD_W_FLASH    ; write flash segment
+  goto      HOOK_CMD_R_EEPROM   ; read eeprom
+  goto      HOOK_CMD_W_EEPROM   ; write eeprom
+  goto      HOOK_CMD_R_CONFIG   ; read config
+  goto      HOOK_CMD_R_CONFIG   ; write config
+
+  ;; ** generic error messages *******
+invalid_cmd               ; received command code is not known or len is bogus
+  movlw     E_INV_CMD
+  call      ack_cmd
+  goto      wait_new_cmd
+
+csum_error                 ; received command has an invalid check sum
+  movlw     E_BAD_CSUM
+  call      ack_cmd
+  goto      wait_new_cmd
+
+address_invalid            ; received command uses invalid address (i.e. not aligned to 16bytes)
+  movlw     E_ADDR_INVALID
+  call      ack_cmd
+  goto      wait_new_cmd
+
+address_prohibited         ; received command uses prohibited address (i.e. FLASH < 0x100)
+  movlw     E_ADDR_PROHIB
+  call      ack_cmd
+  goto      wait_new_cmd
+
+  ;; ** generic command handlers ************
+  ;; ** identify *******
+cmd_identify
+  clrf      csum
+  movf      combuff,w
+  call      com_tx_byte
+
+  movlw     .19
+  call      com_tx_byte
+
+  movlw     E_OK
+  call      com_tx_byte
+
+  movlw     VERSION_MIN
+  call      com_tx_byte
+  movlw     VERSION_MAJ
+  call      com_tx_byte
+
+  movlw     NAME_0
+  call      com_tx_byte
+  movlw     NAME_1
+  call      com_tx_byte
+  movlw     NAME_2
+  call      com_tx_byte
+
+  movlw     DEVID_L
+  call      com_tx_byte
+  movlw     DEVID_H
+  call      com_tx_byte
+
+  movlw     FLASH_SIZE_L
+  call      com_tx_byte
+  movlw     FLASH_SIZE_H
+  call      com_tx_byte
+  movlw     FSS
+  call      com_tx_byte
+
+  movlw     EEPROM_SIZE_L
+  call      com_tx_byte
+  movlw     EEPROM_SIZE_H
+  call      com_tx_byte
+  movlw     MESS
+  call      com_tx_byte
+
+  movlw     SUPPORTED_L
+  call      com_tx_byte
+  movlw     SUPPORTED_H
+  call      com_tx_byte
+
+  movf      csum,w
+  call      com_tx_byte
+  goto      wait_new_cmd
+
+  ;; ** boot *******
+cmd_boot
+  movlw     E_OK
+  call      ack_cmd
+  goto      USERVECT
+
+  ;; ** not implemented commands *******
+cmd_not_impl
+  movlw     E_NOT_IMPL
+  call      ack_cmd
+  goto      wait_new_cmd
diff --git a/software/pic.bootloader/ihexpic.py b/software/pic.bootloader/ihexpic.py
new file mode 100644
index 0000000..e30204c
--- /dev/null
+++ b/software/pic.bootloader/ihexpic.py
@@ -0,0 +1,405 @@
+#  spreadspace pic utils
+#
+#
+#  Copyright (C) 2011 Christian Pointner <equinox@spreadspace.org>
+#
+#  This file is part of spreadspace pic utils.
+#
+#  spreadspace pic utils is free software: you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation, either version 3 of the License, or
+#  any later version.
+#
+#  spreadspace pic utils is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with spreadspace pic utils. If not, see <http://www.gnu.org/licenses/>.
+#
+#*********************************************************************
+# This is based on IntelHex 1.4
+#  which can be found at: http://www.bialix.com/intelhex/
+#
+#
+# Copyright (c) 2005-2012, Alexander Belchenko
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms,
+# with or without modification, are permitted provided
+# that the following conditions are met:
+#
+# * Redistributions of source code must retain
+#   the above copyright notice, this list of conditions
+#   and the following disclaimer.
+# * Redistributions in binary form must reproduce
+#   the above copyright notice, this list of conditions
+#   and the following disclaimer in the documentation
+#   and/or other materials provided with the distribution.
+# * Neither the name of the author nor the names
+#   of its contributors may be used to endorse
+#   or promote products derived from this software
+#   without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
+# BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+# AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+# IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+# OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+# OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+# STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+# EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#*********************************************************************
+
+'''Intel HEX file format reader and writer for PIC Microcontroller.'''
+
+
+from array import array
+from binascii import hexlify, unhexlify
+from bisect import bisect_right
+import sys
+
+
+class IHexPic(object):
+    ''' Intel HEX file reader for PIC Microcontroller. '''
+
+    def __init__(self):
+        # private members
+        self._buf = {}
+        self._offset = 0
+
+    def _decode_record(self, s, line=0):
+        '''Decode one record of HEX file.
+
+        @param  s       line with HEX record.
+        @param  line    line number (for error messages).
+
+        @raise  EndOfFile   if EOF record encountered.
+        '''
+        s = s.rstrip('\r\n')
+        if not s:
+            return          # empty line
+
+        if s[0] == ':':
+            try:
+                bin = array('B', unhexlify(str(s[1:])))
+            except (TypeError, ValueError):
+                # this might be raised by unhexlify when odd hexascii digits
+                raise HexRecordError(line=line)
+            length = len(bin)
+            if length < 5:
+                raise HexRecordError(line=line)
+        else:
+            raise HexRecordError(line=line)
+
+        record_length = bin[0]
+        if length != (5 + record_length):
+            raise RecordLengthError(line=line)
+        if record_length%2 != 0:
+            raise RecordLengthError(line=line)
+
+        addr = bin[1]*256 + bin[2]
+        if addr%2 != 0:
+            raise RecordAlignmentError(line=line)
+
+        record_type = bin[3]
+        if not (0 <= record_type <= 5):
+            raise RecordTypeError(line=line)
+
+        crc = sum(bin)
+        crc &= 0x0FF
+        if crc != 0:
+            raise RecordChecksumError(line=line)
+
+        if record_type == 0:
+            # data record
+            addr += self._offset
+            for i in xrange(4, 4+record_length, 2):
+                addr16 = addr/2
+                if not self._buf.get(addr16, None) is None:
+                    raise AddressOverlapError(address=addr16, line=line)
+                self._buf[addr16] = bin[i] + (bin[i+1]<<8)
+                addr += 2   # FIXME: addr should be wrapped
+                            # BUT after 02 record (at 64K boundary)
+                            # and after 04 record (at 4G boundary)
+
+        elif record_type == 1:
+            # end of file record
+            if record_length != 0:
+                raise EOFRecordError(line=line)
+            raise _EndOfFile
+
+        elif record_type == 2:
+            # Extended 8086 Segment Record
+            if record_length != 2 or addr != 0:
+                raise ExtendedSegmentAddressRecordError(line=line)
+            self._offset = (bin[4]*256 + bin[5]) * 16
+
+        elif record_type == 4:
+            # Extended Linear Address Record
+            if record_length != 2 or addr != 0:
+                raise ExtendedLinearAddressRecordError(line=line)
+            self._offset = (bin[4]*256 + bin[5]) * 65536
+
+        else:
+            raise UnsupportedRecordTypeError(type=record_type, line=line)
+
+
+    def load_from_file(self, fobj):
+        """Load hex file into internal buffer.
+
+        @param  fobj        file name or file-like object
+        """
+        if getattr(fobj, "read", None) is None:
+            fobj = open(fobj, "r")
+            fclose = fobj.close
+        else:
+            fclose = None
+
+        line = 0
+
+        try:
+            decode = self._decode_record
+            try:
+                for s in fobj:
+                    line += 1
+                    decode(s, line)
+            except _EndOfFile:
+                pass
+        finally:
+            if fclose:
+                fclose()
+
+    def load_from_dict(self, dikt):
+        """Load data from dictionary. Dictionary should contain int keys
+        representing addresses. Values should be the data to be stored in
+        those addresses in unsigned char form (i.e. not strings).
+
+        The contents of the dict will be merged with this object and will
+        overwrite any conflicts.
+        """
+        s = dikt.copy()
+        for k in s.keys():
+            if type(k) not in (int, long) or k < 0:
+                raise ValueError('Source dictionary should have only int keys')
+        self._buf.update(s)
+
+    def write_to_file(self, f):
+        """Write data to file f in HEX format.
+
+        @param  f                   filename or file-like object for writing
+        """
+        fwrite = getattr(f, "write", None)
+        if fwrite:
+            fobj = f
+            fclose = None
+        else:
+            fobj = file(f, 'w')
+            fwrite = fobj.write
+            fclose = fobj.close
+
+        # Translation table for uppercasing hex ascii string.
+        # timeit shows that using hexstr.translate(table)
+        # is faster than hexstr.upper():
+        # 0.452ms vs. 0.652ms (translate vs. upper)
+        if sys.version_info[0] >= 3:
+            table = bytes(range(256)).upper()
+        else:
+            table = ''.join(chr(i).upper() for  i in range(256))
+
+
+        # data
+        addresses = self._buf.keys()
+        addresses.sort()
+        addr_len = len(addresses)
+        if addr_len:
+            minaddr = addresses[0]
+            maxaddr = addresses[-1]
+
+            if maxaddr > 65535/2:
+                need_offset_record = True
+            else:
+                need_offset_record = False
+            high_ofs = 0
+
+            cur_addr = minaddr
+            cur_ix = 0
+
+            while cur_addr <= maxaddr:
+                if need_offset_record:
+                    bin = array('B', str('\0'*7))
+                    bin[0] = 2      # reclen
+                    bin[1] = 0      # offset msb
+                    bin[2] = 0      # offset lsb
+                    bin[3] = 4      # rectype
+                    high_ofs = int(cur_addr>>16)
+                    b = divmod(high_ofs*2, 256)
+                    bin[4] = b[0]   # msb of high_ofs
+                    bin[5] = b[1]   # lsb of high_ofs
+                    bin[6] = (-sum(bin)) & 0x0FF    # chksum
+                    fwrite(':' +
+                           str(hexlify(bin.tostring()).translate(table)) +
+                           '\n')
+
+                while True:
+                    # produce one record
+                    low_addr = cur_addr & 0x0FFFF
+                    # chain_len off by 1
+                    chain_len = min(7, 65535-low_addr, maxaddr-cur_addr)
+
+                    # search continuous chain
+                    stop_addr = cur_addr + chain_len
+                    if chain_len:
+                        ix = bisect_right(addresses, stop_addr,
+                                          cur_ix,
+                                          min(cur_ix+chain_len+1, addr_len))
+                        chain_len = ix - cur_ix     # real chain_len
+                        # there could be small holes in the chain
+                        # but we will catch them by try-except later
+                        # so for big continuous files we will work
+                        # at maximum possible speed
+                    else:
+                        chain_len = 1               # real chain_len
+
+                    bin = array('B', str('\0'*(5+(chain_len*2))))
+                    b = divmod(low_addr*2, 256)
+                    bin[1] = b[0]   # msb of low_addr
+                    bin[2] = b[1]   # lsb of low_addr
+                    bin[3] = 0          # rectype
+                    try:    # if there is small holes we'll catch them
+                        for i in range(chain_len):
+                            bin[4+(i*2)] = self._buf[cur_addr+i] & 0x00FF
+                            bin[4+(i*2)+1] = self._buf[cur_addr+i] >> 8
+                    except KeyError:
+                        # we catch a hole so we should shrink the chain
+                        chain_len = i
+                        bin = bin[:5+(i*2)]
+                    bin[0] = chain_len*2
+                    bin[4+(chain_len*2)] = (-sum(bin)) & 0x0FF    # chksum
+                    fwrite(':' +
+                           str(hexlify(bin.tostring()).translate(table)) +
+                           '\n')
+
+                    # adjust cur_addr/cur_ix
+                    cur_ix += chain_len
+                    if cur_ix < addr_len:
+                        cur_addr = addresses[cur_ix]
+                    else:
+                        cur_addr = maxaddr + 1
+                        break
+                    high_addr = int(cur_addr>>16)
+                    if high_addr > high_ofs:
+                        break
+
+        # end-of-file record
+        fwrite(":00000001FF\n")
+        if fclose:
+            fclose()
+
+    def get_lowest_addr(self):
+        return sorted(self._buf.keys())[0]
+
+    def get_highest_addr(self):
+        return sorted(self._buf.keys())[-1]
+
+    def items(self):
+        return self._buf.items()
+
+    def __getitem__(self, addr):
+        t = type(addr)
+        if t in (int, long):
+            if addr < 0:
+                raise TypeError('Address should be >= 0.')
+            return self._buf(addr, 0xFFFF)
+        else:
+            raise TypeError('Address has unsupported type: %s' % t)
+
+
+##
+# IHexPic Errors Hierarchy:
+#
+#  IHexPicError    - basic error
+#       HexReaderError  - general hex reader error
+#           AddressOverlapError - data for the same address overlap
+#           HexRecordError      - hex record decoder base error
+#               RecordLengthError    - record has invalid length
+#               RecordTypeError      - record has invalid type (RECTYP)
+#               RecordChecksumError  - record checksum mismatch
+#               EOFRecordError              - invalid EOF record (type 01)
+#               ExtendedAddressRecordError  - extended address record base error
+#                   ExtendedSegmentAddressRecordError   - invalid extended segment address record (type 02)
+#                   ExtendedLinearAddressRecordError    - invalid extended linear address record (type 04)
+#               UnsupportedRecordError              - invalid/unsupported record type
+#       _EndOfFile  - it's not real error, used internally by hex reader as signal that EOF record found
+
+class IHexPicError(Exception):
+    '''Base Exception class for IHexPic module'''
+
+    _fmt = 'IHexPic base error'   #: format string
+
+    def __init__(self, msg=None, **kw):
+        """Initialize the Exception with the given message.
+        """
+        self.msg = msg
+        for key, value in kw.items():
+            setattr(self, key, value)
+
+    def __str__(self):
+        """Return the message in this Exception."""
+        if self.msg:
+            return self.msg
+        try:
+            return self._fmt % self.__dict__
+        except (NameError, ValueError, KeyError), e:
+            return 'Unprintable exception %s: %s' \
+                % (repr(e), str(e))
+
+class _EndOfFile(IHexPicError):
+    """Used for internal needs only."""
+    _fmt = 'EOF record reached -- signal to stop read file'
+
+
+class HexReaderError(IHexPicError):
+    _fmt = 'Hex reader base error'
+
+class AddressOverlapError(HexReaderError):
+    _fmt = 'Hex file has data overlap at address 0x%(address)X on line %(line)d'
+
+
+class HexRecordError(HexReaderError):
+    _fmt = 'Hex file contains invalid record at line %(line)d'
+
+
+class RecordLengthError(HexRecordError):
+    _fmt = 'Record at line %(line)d has invalid length'
+
+class RecordAlignmentError(HexRecordError):
+    _fmt = 'Record at line %(line)d has invalid adress (not 16bit aligned)'
+
+class RecordTypeError(HexRecordError):
+    _fmt = 'Record at line %(line)d has invalid record type'
+
+class RecordChecksumError(HexRecordError):
+    _fmt = 'Record at line %(line)d has invalid checksum'
+
+class EOFRecordError(HexRecordError):
+    _fmt = 'File has invalid End-of-File record'
+
+class UnsupportedRecordError(HexRecordError):
+    _fmt = 'File has unsupported record type %(type)d at line %(line)d'
+
+
+class ExtendedAddressRecordError(HexRecordError):
+    _fmt = 'Base class for extended address exceptions'
+
+class ExtendedSegmentAddressRecordError(ExtendedAddressRecordError):
+    _fmt = 'Invalid Extended Segment Address Record at line %(line)d'
+
+class ExtendedLinearAddressRecordError(ExtendedAddressRecordError):
+    _fmt = 'Invalid Extended Linear Address Record at line %(line)d'
diff --git a/software/pic.bootloader/proto.txt b/software/pic.bootloader/proto.txt
new file mode 100644
index 0000000..0e35e1e
--- /dev/null
+++ b/software/pic.bootloader/proto.txt
@@ -0,0 +1,200 @@
+Command List:
+=============
+
+  code | command
+ ------+------------
+    1  | identify
+    2  | boot
+    3  | reset
+    4  | read flash
+    5  | write flash
+    6  | read eeprom
+    7  | write eeprom
+    8  | read config
+    9  | write config
+
+
+Description:
+------------
+
+Every command consits of one byte command code, one byte length which counts all
+bytes of the command including the command code and checksum. The length is followed
+by zero or more data and a XOR checksum over all bytes sent. All data is
+transferred LSB first (aka little endian). All addresses and words are 2bytes long.
+Every answer to a command starts with the command code a length field which counts all
+bytes of the answer, one byte return value optionally some data and a checksum
+(XOR over all bytes received).
+The return codes have the following meaning:
+
+  code | Error
+ ------+-------------
+    0  | OK
+    1  | invalid command
+    2  | bad checksum
+    3  | not implemented
+    4  | flash write error
+    5  | address invalid
+    6  | address prohibited
+    5  | value out of bounds
+
+identify:
+~~~~~~~~~
+  command:
+    1 | len=3 | <csum>
+
+  answer:
+    1 | len=19 | <ret> | version | name | devid | fs | fss | es | mess | supported | <csum>
+
+      version:
+         2bytes, protocol version
+         It is an error if the major version (MSB) is different (hence any
+         protocol update must change the major version of the bootloader).
+
+      name:
+         3bytes, a descriptive name of the device.
+         The downloader has to compare this name with the device name supplied
+         via commandline and stop in case they don't match
+
+      devid:
+         2bytes, device id of the PIC
+         The downlaoder may use this id to check if it talks to the right bootloader
+
+      fs:
+         2bytes, flash size
+         The size of the flash in code words.
+
+      fss:
+         1byte, flash segment size
+         The number of words of one flash segment which has to be written at once.
+         If less than <fss> should be updated the downloader has to perform a read
+         operation first.
+
+      es:
+         2bytes, eeprom size
+         The size of the eeprom in bytes.
+
+      mess:
+         1byte, maximum eeprom segment size
+         This represents the maximum number of eeprom bytes which may be written or
+         read at once. Unlike <fss> value it is ok to write or read less than <mess>
+         bytes.
+
+      supported:
+         2bytes, a bitmap showing supported commands
+         The commands 'identify' and 'boot' are always supported by the bootloader,
+         others may not (i.e.: not all PICs allow to update the configurtion words)
+
+           bit | command
+          -----+----------
+            0  | reset
+            1  | read flash
+            2  | write flash
+            3  | read eeprom
+            4  | write eeprom
+            5  | read config
+            6  | write config
+
+
+boot:
+~~~~~
+
+  command:
+    2 | len=3 | <csum>
+
+  answer:
+    2 | len=4 | <ret> | <csum>
+
+  This instucts the bootloader to boot to the user application directly (no reset)
+
+
+reset:
+~~~~~~
+
+  command:
+    3 | len=3 | <csum>
+
+  answer:
+    3 | len=4 | <ret> | <csum>
+
+  The device performs a reboot. If the boot condition (i.e.: port pin) is not met
+  this instructs the device to boot to the user application.
+
+
+read flash:
+~~~~~~~~~~~
+
+  command:
+    4 | len=5 | addr | <csum>
+
+  answer:
+    4 | len=4+2*<fss> | <ret> | data | <csum>
+
+  The bootloader reads <fss> words from flash address <addr> and returns it as
+  <data>.
+
+
+write flash:
+~~~~~~~~~~~~
+
+  command:
+    5 | len=5+2*<fss> | addr | data | <csum>
+
+  answer:
+    5 | len=4 | <ret> | <csum>
+
+  The bootloader writes <data> (which has to contain exactly <fss> words) to address
+  <addr> inside the flash. The start address has to be aligned to <fss> boundaries.
+  Before writing the memory region will be erased. If there are words which shouldn't
+  be altered the downloader has to read these words first and reprogram the whole segment.
+
+
+read eeprom:
+~~~~~~~~~~~~
+
+  command:
+    6 | len=5 | addr | len | <csum>
+
+  answer:
+    6 | len=4+<len> | <ret> | data | <csum>
+
+  The bootloader reads <len> bytes from eeprom at address <addr> and returns it as
+  <data>. len is 1byte long.
+
+
+write eeprom:
+~~~~~~~~~~~~~
+
+  command:
+    7 | len=4+len(data) | addr | data | <csum>
+
+  answer:
+    7 | len=4 | <ret> | <csum>
+
+  The bootloader writes <data> (which has to contain exactly <len>-4 bytes) to address
+  <addr> inside the eeprom. len is 1byte long and the value must not exceed <mess> bytes.
+
+
+read config:
+~~~~~~~~~~~~
+
+  command:
+    8 | len=3 | nr | <csum>
+
+  answer:
+    8 | len=6 | <ret> | word | <csum>
+
+  The bootloader reads and returns the configuration word number <nr>. <nr> is one
+  byte long.
+
+
+write config:
+~~~~~~~~~~~~~
+
+  command:
+    9 | len=5 | nr | word | <csum>
+
+  answer:
+    9 | len=4 | <ret> | <csum>
+
+  The bootloader writes <word> onto configuration word number <nr>. <nr> is one
+  byte long.