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|
;;
;; 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_OFF & _CPD_OFF & _CP_OFF & _MCLRE_OFF & _PWRTE_OFF & _WDT_OFF & _INTOSC
__config _CONFIG2, _BOR21V & _WRT_256
;; -------------------------------------
;; DEFINES
#define BOOTPIN PORTC,7
USERVECT EQU H'100'
ISRVECT EQU USERVECT + H'4'
VERSION_MAJ EQU .0
VERSION_MIN EQU .1
DEVID_H EQU H'20'
DEVID_L EQU H'82'
FSS EQU .8
MESS_H EQU .0
MESS_L EQU .64
SUPPORTED_H EQU .0
SUPPORTED_L EQU b'00011111' ; reset, read/write flash, read/write eeprom
;; 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
;; Variables
combuff EQU H'0020'
combuff_end EQU H'006F'
current_cmdlen EQU H'0070'
csum EQU H'0071'
flags EQU H'007D'
#define F_INVALID_CMD flags,0
#define F_WEEP flags,7
cnt2 EQU H'007E'
cnt1 EQU H'007F'
;; -------------------------------------
;; Boot test
org .0
;; btfsc BOOTPIN
;; goto USERVECT
goto boot
;; -------------------------------------
;; goto user ISR
org .4
isr
goto ISRVECT
;; -------------------------------------
;; Bootloader (Subroutines)
uart_tx_byte
btfss PIR1,TXIF
goto uart_tx_byte
movwf TXREG
xorwf csum,f
return
send_answer
movwf cnt1
movlw combuff
movwf FSR
clrf csum
send_answer_next
movf INDF,w
call uart_tx_byte
incf FSR,f
decfsz cnt1,f
goto send_answer_next
movf csum,w
call uart_tx_byte
return
check_cmd_code
movf combuff,w
sublw CMD_MAX
btfss STATUS,C
bsf F_INVALID_CMD
return
get_cmdlen
addwf PCL,f
retlw .0 ; invalid
retlw .1 ; identify: <csum>
retlw .1 ; boot: <csum>
retlw .1 ; reset: <csum>
retlw .3 ; read flash: addr | <csum>
retlw .3 + .2*FSS ; write flash: addr | data | <csum>
retlw .5 ; read eeprom: addr | len | <csum>
retlw .5 ; write eeprom: addr | len | data | <csum> (minimal)
retlw .2 ; read config: nr | <csum>
retlw .4 ; write config: nr | word | <csum>
get_name
addwf PCL,f
nop
retlw 'c'
retlw 'i'
retlw 'p'
retlw '-'
retlw 'd'
retlw 'a'
retlw 'e'
retlw 'r'
retlw 'p'
retlw 's'
;; -------------------------------------
;; Bootloader (init)
boot
;; 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
wait_new_cmd
movlw combuff
movwf FSR
clrf combuff
clrf current_cmdlen
clrf flags
wait_cmd
btfsc PIR1,RCIF
goto uart_rx_byte
btfsc RCSTA,OERR
goto uart_rx_oe
goto wait_cmd
uart_rx_oe ; recover from overflow
bcf RCSTA,CREN
bsf RCSTA,CREN
goto wait_new_cmd
uart_rx_byte ; process received command
btfsc RCSTA,FERR
goto uart_rx_fe
movf RCREG,w
movwf INDF
incf FSR,f
movf current_cmdlen,f
btfsc STATUS,Z
goto new_cmd
decfsz current_cmdlen,f
goto wait_cmd
goto exec_cmd
uart_rx_fe ; recover from framing error
movf RCREG,w
goto wait_new_cmd
new_cmd ; got new command code
call check_cmd_code
btfsc F_INVALID_CMD
goto invalid_cmd
movf combuff,w
call get_cmdlen
movwf current_cmdlen
goto wait_cmd
invalid_cmd ; received command code is not known
movlw E_INV_CMD
movwf combuff + .1
movlw .2
call send_answer
goto wait_new_cmd
exec_cmd ; command is correct and complete
;; TODO: check csum -> csum for write eeprom will not be correct because
;; it isn't finished yet....???
movf combuff,w ; dispatch commands
addwf PCL,f
nop
goto cmd_identify
goto cmd_boot
goto cmd_reset
goto cmd_r_flash
goto cmd_w_flash
goto cmd_r_eeprom
goto cmd_w_eeprom
goto cmd_r_config
goto cmd_w_config
goto wait_new_cmd
;; ** Command Handlers ********************
;; ** identify *******
cmd_identify
clrf csum
movf combuff,w
call uart_tx_byte
movlw E_OK
call uart_tx_byte
movlw VERSION_MIN
call uart_tx_byte
movlw VERSION_MAJ
call uart_tx_byte
movlw .10
movwf cnt1
cmd_identify_send_name
movf cnt1,w
call get_name
call uart_tx_byte
decfsz cnt1,f
goto cmd_identify_send_name
movlw DEVID_L
call uart_tx_byte
movlw DEVID_H
call uart_tx_byte
movlw FSS
call uart_tx_byte
movlw MESS_L
call uart_tx_byte
movlw MESS_H
call uart_tx_byte
movlw SUPPORTED_L
call uart_tx_byte
movlw SUPPORTED_H
call uart_tx_byte
movf csum,w
call uart_tx_byte
goto wait_new_cmd
;; ** boot *******
cmd_boot
movlw E_OK
movwf combuff + .1
movlw .2
call send_answer
goto USERVECT
;; ** reset *******
cmd_reset
movlw E_OK
movwf combuff + .1
movlw .2
call send_answer
movlw b'00000001'
movwf WDTCON ; why does this not work?????
cmd_reset_wait
goto cmd_reset_wait
;; ** read flash *******
cmd_r_flash
call read_flash_segment
call send_answer
goto wait_new_cmd
;; ** write flash *******
cmd_w_flash
;; call write_flash_segment
movlw E_ADDR_INVALID
movwf combuff + .1
movlw .2
call send_answer
goto wait_new_cmd
;; ** read eeprom *******
cmd_r_eeprom
;; call read_eeprom
movlw E_ADDR_INVALID
movwf combuff + .1
movlw .2
call send_answer
goto wait_new_cmd
;; ** write eeprom *******
cmd_w_eeprom
btfss F_WEEP
goto cmd_w_eeprom_len
;; call write_eeprom
movlw E_ADDR_INVALID
movwf combuff + .1
movlw .2
call send_answer
goto wait_new_cmd
cmd_w_eeprom_len
movf combuff + .3,w
movwf current_cmdlen
bsf F_WEEP
goto wait_cmd
;; ** not implemented commands *******
cmd_r_config
cmd_w_config
movlw E_NOT_IMPL
movwf combuff + .1
movlw .2
call send_answer
goto wait_new_cmd
;; -------------------------------------
;; actual flash/eeprom functions
read_flash_segment
movlw FSS
movwf cnt1
movlw b'01011000'
movwf STATUS
movlw combuff + .1
movwf FSR
movf INDF,w
movwf EEADR
incf FSR,f
movf INDF,w
movwf EEADRH
read_flash_segment_loop
bsf STATUS,RP0
bsf EECON1,EEPGD
bsf EECON1,RD
nop
nop
bcf STATUS,RP0
movf EEDAT,w
movwf INDF
incf FSR,f
movf EEDATH,w
movwf INDF
incf FSR,f
incfsz EEADR,f
goto read_flash_segment_next
incf EEADRH,f
read_flash_segment_next
decfsz cnt1,f
goto read_flash_segment_loop
bcf STATUS,RP1
clrf combuff + .1 ; = E_OK
retlw .2 + 2*FSS ; bytes to send
;; -------------------------------------
;; -------------------------------------
;; dummy user code
org USERVECT
;; goto USERVECT
bsf STATUS,RP0
bcf TRISD,0
bcf STATUS,RP0
userloop
movlw b'00000001'
xorwf PORTD,f
movlw .255
movwf cnt1
usercnt1
movlw .255
movwf cnt2
usercnt2
decfsz cnt2,f
goto usercnt2
decfsz cnt1,f
goto usercnt1
goto userloop
;; -------------------------------------
;; END
end
|
