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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 & _XT_OSC
;; __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'
;; -------------------------------------
;; 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'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
btfss 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??
movwf TMP ; TODO: move to input string
;; TODO: check if command is finished and jump
;; to 'exec_cmd'
return
uart_rx_fe
movf RCREG,w
goto wait_cmd
exec_cmd
;; TODO: execute received command
goto USERVECT
;; -------------------------------------
;; dummy user code
org USERVECT
goto USERVECT
;; -------------------------------------
;; END
end
|
