1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
|
;;
;; 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
MESS EQU 64
;; 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
;; CMD codes
CCMD_IDENTIFY EQU 'i'
CMD_IDENTIFY EQU 0
CCMD_BOOT EQU 'b'
CMD_BOOT EQU 1
CCMD_RESET EQU 'r'
CMD_RESET EQU 2
CCMD_R_FLASH EQU 'f'
CMD_R_FLASH EQU 3
CCMD_W_FLASH EQU 'F'
CMD_W_FLASH EQU 4
CCMD_R_EEPROM EQU 'e'
CMD_R_EEPROM EQU 5
CCMD_W_EEPROM EQU 'E'
CMD_W_EEPROM EQU 6
CCMD_R_CONFIG EQU 'c'
CMD_R_CONFIG EQU 7
CCMD_W_CONFIG EQU 'C'
CMD_W_CONFIG EQU 8
CMD_INVALID EQU H'FF'
;; Variables
inbuff EQU H'0020'
inbuff_end EQU H'006F'
current_cmd EQU H'0070'
current_cmdlen EQU H'0071'
cnt1 EQU H'0070'
cnt2 EQU H'0071'
;; -------------------------------------
;; 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
translate_cmd_codes
xorlw CCMD_IDENTIFY
btfsc STATUS,Z
retlw CMD_IDENTIFY
xorlw CCMD_BOOT ^ CCMD_IDENTIFY
btfsc STATUS,Z
retlw CMD_BOOT
xorlw CCMD_RESET ^ CCMD_BOOT
btfsc STATUS,Z
retlw CMD_RESET
xorlw CCMD_R_FLASH ^ CCMD_RESET
btfsc STATUS,Z
retlw CMD_R_FLASH
xorlw CCMD_W_FLASH ^ CCMD_R_FLASH
btfsc STATUS,Z
retlw CMD_W_FLASH
xorlw CCMD_R_EEPROM ^ CCMD_W_FLASH
btfsc STATUS,Z
retlw CMD_R_EEPROM
xorlw CCMD_W_EEPROM ^ CCMD_R_EEPROM
btfsc STATUS,Z
retlw CMD_W_EEPROM
xorlw CCMD_R_CONFIG ^ CCMD_W_EEPROM
btfsc STATUS,Z
retlw CMD_R_CONFIG
xorlw CCMD_W_CONFIG ^ CCMD_R_CONFIG
btfsc STATUS,Z
retlw CMD_W_CONFIG
retlw CMD_INVALID
get_cmdlen
addwf PCL,f
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>
;; -------------------------------------
;; 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
bcf TRISD,0 ; DEBUG!!!!
;; bank 0
bcf STATUS,RP0
movlw b'10010000' ; enable Serial Port, 8bit, enable continues receive, disable address detection
movwf RCSTA
bsf PORTD,0 ; DEBUG!!!!
wait_new_cmd
movlw inbuff
movwf FSR
movlw CMD_INVALID
movwf current_cmd
clrf current_cmdlen
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_new_cmd
uart_rx_byte
btfsc RCSTA,FERR
goto uart_rx_fe
movf RCREG,w ; TODO: check parity??
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
movf RCREG,w
goto wait_new_cmd
new_cmd
call translate_cmd_codes
movwf current_cmd
xorlw CMD_INVALID
btfsc STATUS,Z
goto invalid_cmd
movf current_cmd,w
call get_cmdlen
movwf current_cmdlen
goto wait_cmd
invalid_cmd
movf inbuff,w
call uart_tx_byte
movlw E_INV_CMD
call uart_tx_byte
movlw E_INV_CMD
xorwf inbuff,w
call uart_tx_byte
goto wait_new_cmd
exec_cmd
;; TODO: execute received command
bcf PORTD,0
movlw .255
movwf cnt1
dbgcnt1
movlw .255
movwf cnt2
dbgcnt2
decfsz cnt2,f
goto dbgcnt2
decfsz cnt1,f
goto dbgcnt1
bsf PORTD,0
goto wait_new_cmd
;; -------------------------------------
;; 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
|