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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'
FSS EQU 8
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
CMD_IDENTIFY EQU 'i'
CMD_BOOT EQU 'b'
CMD_RESET EQU 'r'
CMD_R_FLASH EQU 'f'
CMD_W_FLASH EQU 'F'
CMD_R_EEPROM EQU 'e'
CMD_W_EEPROM EQU 'E'
CMD_R_CONFIG EQU 'c'
CMD_W_CONFIG EQU 'C'
CNT1 EQU H'0020'
CNT2 EQU H'0021'
;; -------------------------------------
;; 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
return
;; -------------------------------------
;; 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_cmd
btfsc PIR1,RCIF
goto uart_rx_byte
btfsc RCSTA,OERR
goto uart_rx_oe
goto wait_cmd
uart_rx_oe
bcf RCSTA,CREN
bsf RCSTA,CREN
goto wait_cmd
uart_rx_byte
btfsc RCSTA,FERR
goto uart_rx_fe
movf RCREG,w ; TODO: check parity??
; TODO: move to input string
;; TODO: check if command is finished and jump
;; to 'exec_cmd'
call uart_tx_byte
goto wait_cmd
goto exec_cmd
uart_rx_fe
movf RCREG,w
goto wait_cmd
exec_cmd
;; TODO: execute received command
goto wait_cmd
;; -------------------------------------
;; dummy user code
org USERVECT
;; goto USERVECT
bsf STATUS,RP0
bcf TRISD,0
bcf STATUS,RP0
userloop
movlw b'00000001'
xorwf TRISD,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
|
