|
0
|
1
|
|
|
2 ; OSTC - diving computer code
|
|
|
3 ; Copyright (C) 2008 HeinrichsWeikamp GbR
|
|
|
4 ; This program is free software: you can redistribute it and/or modify
|
|
|
5 ; it under the terms of the GNU General Public License as published by
|
|
|
6 ; the Free Software Foundation, either version 3 of the License, or
|
|
|
7 ; (at your option) any later version.
|
|
|
8 ; This program is distributed in the hope that it will be useful,
|
|
|
9 ; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
|
10 ; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
|
11 ; GNU General Public License for more details.
|
|
|
12 ; You should have received a copy of the GNU General Public License
|
|
|
13 ; along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
14 ; provides routines for external EEPROM via I2C
|
|
|
15 ; written by: Matthias Heinrichs, info@heinrichsweikamp.com
|
|
|
16 ; written: 10/30/05
|
|
|
17 ; last updated: 08/21/06
|
|
|
18 ; known bugs:
|
|
|
19 ; ToDo: use 2nd 32KB from external EEPROM for something
|
|
|
20
|
|
|
21 incf_eeprom_address macro ext_ee_temp1 ; Will increase eeprom_address:2 with the 8Bit value "ext_ee_temp1" and takes
|
|
|
22 movlw ext_ee_temp1 ; care of bank switching at 0x8000
|
|
|
23 call incf_eeprom_address0
|
|
|
24 endm
|
|
|
25
|
|
|
26 incf_eeprom_address0:
|
|
|
27 movwf ext_ee_temp1
|
|
|
28 incf_eeprom_address1:
|
|
|
29 movlw d'1' ; increase address
|
|
|
30 addwf eeprom_address+0,F
|
|
|
31 movlw d'0'
|
|
|
32 addwfc eeprom_address+1,F
|
|
|
33 btfss eeprom_address+1,7 ; at address 8000?
|
|
|
34 bra incf_eeprom_address2 ; No, continue
|
|
|
35
|
|
|
36 ; Yes, clear eeprom_address:2
|
|
|
37 clrf eeprom_address+0 ; Clear eeprom address
|
|
|
38 clrf eeprom_address+1
|
|
|
39
|
|
|
40 incf_eeprom_address2:
|
|
|
41 decfsz ext_ee_temp1,F ; All done?
|
|
|
42 bra incf_eeprom_address1 ; No, continue
|
|
|
43 return ; Done.
|
|
|
44
|
|
|
45 decf_eeprom_address macro ext_ee_temp1 ; Will decrease eeprom_address:2 with the 8Bit value "ext_ee_temp1" and takes
|
|
|
46 movlw ext_ee_temp1 ; care of bank switching at 0x8000
|
|
|
47 call decf_eeprom_address0
|
|
|
48 endm
|
|
|
49
|
|
|
50 decf_eeprom_address0:
|
|
|
51 movwf ext_ee_temp1
|
|
|
52 decf_eeprom_address1:
|
|
|
53 movlw d'1' ; decrease address
|
|
|
54 subwf eeprom_address+0,F
|
|
|
55 movlw d'0'
|
|
|
56 subwfb eeprom_address+1,F
|
|
|
57
|
|
|
58 btfss eeprom_address+1,7 ; at address 8000?
|
|
|
59 bra decf_eeprom_address2 ; No, continue
|
|
|
60
|
|
|
61 movlw b'01111111' ; yes, reset highbyte
|
|
|
62 movwf eeprom_address+1
|
|
|
63
|
|
|
64 decf_eeprom_address2:
|
|
|
65 decfsz ext_ee_temp1,F ; All done?
|
|
|
66 bra decf_eeprom_address1 ; No, continue
|
|
|
67 return ; Done.
|
|
|
68
|
|
|
69
|
|
|
70 write_external_eeprom: ; data in WREG
|
|
|
71 ; increase address eeprom_address+0:eeprom_address+1 after write
|
|
|
72 ; with banking after 7FFF
|
|
81
|
73 #ifdef TESTING
|
|
|
74 ; When Simulating with MPLabSIM, there is no way to emulate external EEPROM...
|
|
|
75 return
|
|
|
76 #endif
|
|
|
77
|
|
0
|
78 rcall I2CWRITE ; writes WREG into EEPROM@eeprom_address
|
|
|
79 movlw d'1' ; increase address
|
|
|
80 addwf eeprom_address+0,F
|
|
|
81 movlw d'0'
|
|
|
82 addwfc eeprom_address+1,F
|
|
|
83 bcf eeprom_overflow
|
|
|
84 btfss eeprom_address+1,7 ; at address 8000?
|
|
|
85 return ; no, return
|
|
|
86
|
|
|
87 clrf eeprom_address+0 ; Clear eeprom address
|
|
|
88 clrf eeprom_address+1
|
|
|
89 bsf eeprom_overflow ; and set overflow bit
|
|
|
90 return
|
|
83
|
91
|
|
0
|
92 write_external_eeprom_block: ; Writes a block of 64Byte (one page in external EEPROM without stop condition
|
|
81
|
93 #ifdef TESTING
|
|
|
94 ; When Simulating with MPLabSIM, there is no way to emulate external EEPROM...
|
|
|
95 return
|
|
|
96 #endif
|
|
|
97
|
|
0
|
98 btfsc eeprom_blockwrite ; Blockwrite continue?
|
|
|
99 rcall I2CWRITE_BLOCK2
|
|
|
100 btfss eeprom_blockwrite ; Blockwrite start?
|
|
|
101 rcall I2CWRITE_BLOCK
|
|
|
102 bsf eeprom_blockwrite ; After the start, do blockwriting for the next 63Bytes!
|
|
|
103
|
|
|
104 movlw d'0' ; increase address
|
|
|
105 incf eeprom_address+0,F
|
|
|
106 addwfc eeprom_address+1,F
|
|
|
107 bcf eeprom_overflow
|
|
|
108
|
|
|
109 btfss eeprom_address+1,7 ; at address 8000
|
|
|
110 return ; no, return
|
|
|
111
|
|
|
112 clrf eeprom_address+0 ; Clear eeprom address
|
|
|
113 clrf eeprom_address+1
|
|
|
114 bsf eeprom_overflow ; and set overflow bit
|
|
|
115 return
|
|
|
116 I2CWRITE_BLOCK:
|
|
|
117 movwf ext_ee_temp1 ; Data byte in WREG
|
|
|
118 bsf SSPCON2,SEN ; Start condition
|
|
|
119 rcall WaitMSSP
|
|
|
120 movlw b'10100110' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
121 movwf SSPBUF ; control byte
|
|
|
122 rcall WaitMSSP
|
|
|
123 rcall I2C_WaitforACK
|
|
|
124 movff eeprom_address+1,SSPBUF ; High Address byte
|
|
|
125 rcall WaitMSSP
|
|
|
126 rcall I2C_WaitforACK
|
|
|
127 movff eeprom_address+0,SSPBUF ; Low Address byte
|
|
|
128 rcall WaitMSSP
|
|
|
129 rcall I2C_WaitforACK
|
|
|
130 I2CWRITE_BLOCK2:
|
|
|
131 movff ext_ee_temp1, SSPBUF ; Data Byte
|
|
|
132 rcall WaitMSSP
|
|
|
133 rcall I2C_WaitforACK
|
|
|
134 return
|
|
|
135
|
|
|
136
|
|
|
137 get_free_EEPROM_location: ; Searches 0xFD, 0xFD, 0xFE and sets Pointer to 0xFE
|
|
81
|
138
|
|
|
139 #ifdef TESTING
|
|
|
140 ; In testing mode, find 0x100 (internal EEPROM) as the first free location...
|
|
|
141 clrf eeprom_address+0 ; Not found in entire EEPROM, set to address 0
|
|
|
142 movlw 0x1
|
|
|
143 movwf eeprom_address+1
|
|
|
144 return
|
|
|
145 #endif
|
|
|
146
|
|
0
|
147 clrf ext_ee_temp1 ; low address counter
|
|
|
148 clrf ext_ee_temp2 ; high address counter
|
|
|
149 bcf second_FD ; clear flags
|
|
|
150 bcf first_FD
|
|
|
151 get_free_EEPROM_location3:
|
|
|
152 bsf SSPCON2, PEN ; Stop condition
|
|
|
153 rcall WaitMSSP
|
|
|
154 bsf SSPCON2,SEN ; Start condition
|
|
|
155 rcall WaitMSSP
|
|
|
156 movlw b'10100110' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
157 movwf SSPBUF ; control byte
|
|
|
158 rcall WaitMSSP
|
|
|
159 btfsc SSPCON2,ACKSTAT
|
|
|
160 bra get_free_EEPROM_location3 ; EEPROM NOT acknowledged, retry!
|
|
|
161
|
|
|
162 movff ext_ee_temp2,SSPBUF ; High Address byte
|
|
|
163 rcall WaitMSSP
|
|
|
164 rcall I2C_WaitforACK
|
|
|
165 movff ext_ee_temp1,SSPBUF ; Low Address byte
|
|
|
166 rcall WaitMSSP
|
|
|
167 rcall I2C_WaitforACK
|
|
|
168
|
|
|
169 bsf SSPCON2,RSEN ; Start condition
|
|
|
170 rcall WaitMSSP
|
|
|
171 movlw b'10100111' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
172 movwf SSPBUF ; control byte
|
|
|
173 rcall WaitMSSP
|
|
|
174 rcall I2C_WaitforACK
|
|
|
175
|
|
|
176 get_free_EEPROM_location2:
|
|
|
177 bsf SSPCON2, RCEN ; Enable recieve mode
|
|
|
178 rcall WaitMSSP
|
|
|
179 btfsc first_FD
|
|
|
180 bra test_2nd_FD
|
|
|
181 bsf first_FD ; found first 0xFD?
|
|
|
182 movlw 0xFD
|
|
|
183 cpfseq SSPBUF
|
|
|
184 bcf first_FD ; No
|
|
|
185 bra get_free_EEPROM_location2c
|
|
|
186
|
|
|
187 test_2nd_FD:
|
|
|
188 btfsc second_FD
|
|
|
189 bra test_FE
|
|
|
190 bsf second_FD ; found second 0xFD?
|
|
|
191 movlw 0xFD
|
|
|
192 cpfseq SSPBUF
|
|
|
193 bra get_free_EEPROM_location2b ;No, clear both flags
|
|
|
194 bra get_free_EEPROM_location2c
|
|
|
195 test_FE:
|
|
|
196 movlw 0xFE ; found the final 0xFE?
|
|
|
197 cpfseq SSPBUF
|
|
|
198 bra get_free_EEPROM_location2b ;No, clear both flags
|
|
|
199 movff ext_ee_temp1,eeprom_address+0 ;Yes, copy ext_ee_temp1->eeprom_address+0 and
|
|
|
200 movff ext_ee_temp2,eeprom_address+1 ;ext_ee_temp2->eeprom_address+1
|
|
|
201 bra get_free_EEPROM_location4 ; Done.
|
|
|
202
|
|
|
203 get_free_EEPROM_location2b:
|
|
|
204 bcf second_FD ; clear both flags!
|
|
|
205 bcf first_FD
|
|
|
206 get_free_EEPROM_location2c:
|
|
|
207 movlw d'1' ; and increase search address
|
|
|
208 addwf ext_ee_temp1,F
|
|
|
209 movlw d'0'
|
|
|
210 addwfc ext_ee_temp2,F
|
|
|
211
|
|
42
|
212 btfsc ext_ee_temp2,7 ; 0x8000 reached?
|
|
0
|
213 bra get_free_EEPROM_location3b ; yes
|
|
|
214
|
|
|
215 bsf SSPCON2, ACKEN ; no, send Ack
|
|
|
216 rcall WaitMSSP
|
|
|
217 bra get_free_EEPROM_location2 ; and continue search
|
|
|
218 get_free_EEPROM_location3b:
|
|
|
219 clrf eeprom_address+0 ; Not found in entire EEPROM, set to address 0
|
|
|
220 clrf eeprom_address+1
|
|
|
221 get_free_EEPROM_location4:
|
|
|
222 bsf SSPCON2, PEN ; Stop
|
|
|
223 rcall WaitMSSP
|
|
|
224
|
|
|
225 bcf second_FD ; clear flags
|
|
|
226 bcf first_FD
|
|
|
227 return ; return
|
|
|
228
|
|
|
229
|
|
|
230 I2CREAD:
|
|
|
231 bsf SSPCON2, PEN ; Stop
|
|
|
232 rcall WaitMSSP
|
|
|
233 bsf SSPCON2,SEN ; Start condition
|
|
|
234 rcall WaitMSSP
|
|
|
235 movlw b'10100110' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
236 movwf SSPBUF ; control byte
|
|
|
237 rcall WaitMSSP
|
|
|
238 btfsc SSPCON2,ACKSTAT
|
|
|
239 bra I2CREAD ; EEPROM NOT acknowledged, retry!
|
|
|
240 movff eeprom_address+1,SSPBUF ; High Address byte
|
|
|
241 rcall WaitMSSP
|
|
|
242 rcall I2C_WaitforACK
|
|
|
243 movff eeprom_address+0,SSPBUF ; Low Address byte
|
|
|
244 rcall WaitMSSP
|
|
|
245 rcall I2C_WaitforACK
|
|
|
246
|
|
|
247 bsf SSPCON2,RSEN ; Start condition
|
|
|
248 rcall WaitMSSP
|
|
|
249 movlw b'10100111' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
250 movwf SSPBUF ; control byte
|
|
|
251 rcall WaitMSSP
|
|
|
252 rcall I2C_WaitforACK
|
|
|
253
|
|
|
254 bsf SSPCON2, RCEN ; Enable recieve mode
|
|
|
255 rcall WaitMSSP
|
|
|
256 movf SSPBUF,W ; copy read byte into WREG
|
|
|
257 bsf SSPCON2, PEN ; Stop
|
|
|
258 rcall WaitMSSP
|
|
|
259 return
|
|
|
260
|
|
|
261 I2CREAD2: ; same as I2CREAD but with automatic address increase
|
|
|
262 rcall I2CREAD
|
|
|
263 movlw d'1'
|
|
|
264 addwf eeprom_address+0,F
|
|
|
265 movlw d'0'
|
|
|
266 addwfc eeprom_address+1,F
|
|
|
267 bcf eeprom_overflow
|
|
|
268 btfss eeprom_address+1,7 ; at 0x8000?
|
|
|
269 return ; no, return
|
|
|
270
|
|
|
271 clrf eeprom_address+0 ; Yes, clear address
|
|
|
272 clrf eeprom_address+1
|
|
|
273 bsf eeprom_overflow ; and set overflow bit
|
|
|
274 return
|
|
|
275
|
|
|
276 I2CWRITE:
|
|
|
277 movwf ext_ee_temp1 ; Data byte
|
|
|
278 bsf SSPCON2,SEN ; Start condition
|
|
|
279 rcall WaitMSSP
|
|
|
280 movlw b'10100110' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
281 movwf SSPBUF ; control byte
|
|
|
282 rcall WaitMSSP
|
|
|
283 rcall I2C_WaitforACK
|
|
|
284 movff eeprom_address+1,SSPBUF ; High Address byte
|
|
|
285 rcall WaitMSSP
|
|
|
286 rcall I2C_WaitforACK
|
|
|
287 movff eeprom_address+0,SSPBUF ; Low Address byte
|
|
|
288 rcall WaitMSSP
|
|
|
289 rcall I2C_WaitforACK
|
|
|
290 movff ext_ee_temp1, SSPBUF ; Data Byte
|
|
|
291 rcall WaitMSSP
|
|
|
292 rcall I2C_WaitforACK
|
|
|
293 bsf SSPCON2,PEN ; Stop condition
|
|
|
294 rcall WaitMSSP
|
|
|
295 WAITMS d'6' ; Write delay
|
|
|
296 return
|
|
|
297
|
|
|
298 I2C_WaitforACK:
|
|
|
299 btfsc SSPCON2,ACKSTAT ; checks for ACK bit from slave
|
|
|
300 rcall I2CFail
|
|
|
301 return
|
|
|
302
|
|
|
303 I2CFail:
|
|
|
304 ostc_debug 'M' ; Sends debug-information to screen if debugmode active
|
|
21
|
305 bsf LED_red
|
|
0
|
306 rcall I2CReset ; I2C Reset
|
|
|
307 bcf PIR1,SSPIF
|
|
|
308 clrf i2c_temp
|
|
|
309 return
|
|
|
310
|
|
|
311 WaitMSSP:
|
|
|
312 decfsz i2c_temp,F ; check for timeout during I2C action
|
|
|
313 bra WaitMSSP2
|
|
|
314 bra I2CFail ; timeout occured
|
|
|
315 WaitMSSP2:
|
|
|
316 btfss PIR1,SSPIF
|
|
|
317 bra WaitMSSP
|
|
|
318 clrf i2c_temp
|
|
|
319 bcf PIR1,SSPIF
|
|
|
320 return
|
|
|
321
|
|
|
322 I2CReset: ; Something went wrong (Slave holds SDA low?)
|
|
|
323 clrf SSPCON1 ; wake-up slave and reset entire module
|
|
|
324 ostc_debug 'N' ; Sends debug-information to screen if debugmode active
|
|
|
325 clrf SSPCON2
|
|
|
326 clrf SSPSTAT
|
|
|
327 bcf TRISC,3 ; SCL OUTPUT
|
|
|
328 bsf TRISC,4 ; SDA Input
|
|
|
329 bcf PORTC,3
|
|
|
330 movlw d'9'
|
|
|
331 movwf i2c_temp ; clock-out 9 clock cycles manually
|
|
|
332 I2CReset_1:
|
|
|
333 bsf PORTC,3 ; SCL=1
|
|
|
334 nop
|
|
|
335 btfsc PORTC,4 ; SDA=1?
|
|
|
336 bra I2CReset_2 ; =1, SDA has been released from slave
|
|
|
337 bcf PORTC,3 ; SCL=0
|
|
|
338 bcf PORTC,3
|
|
|
339 decfsz i2c_temp,F
|
|
|
340 bra I2CReset_1 ; check for nine clock cycles
|
|
|
341 I2CReset_2:
|
|
|
342 bsf TRISC,3 ; SCL Input
|
|
|
343 clrf SSPCON1 ; set I²C Mode
|
|
|
344 WAITMS d'10' ; Reset-Timeout for I2C devices
|
|
|
345 movlw b'00000000'
|
|
|
346 movwf SSPSTAT
|
|
|
347 movlw b'00101000'
|
|
|
348 movwf SSPCON1
|
|
|
349 movlw b'00000000'
|
|
|
350 movwf SSPCON2
|
|
|
351 movlw d'8' ; 400kHz I2C clock @ 16MHz Fcy
|
|
|
352 movwf SSPADD
|
|
21
|
353 bcf LED_red
|
|
0
|
354 ostc_debug 'O' ; Sends debug-information to screen if debugmode active
|
|
|
355 return
|
|
53
|
356
|
|
|
357 ;I2C_TX:
|
|
|
358 ; movwf i2c_temp2 ; Data byte
|
|
|
359 ; bsf SSPCON2,SEN ; Start condition
|
|
|
360 ; rcall WaitMSSP
|
|
|
361 ; movlw b'10010000' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
362 ; movwf SSPBUF ; control byte
|
|
|
363 ; rcall WaitMSSP
|
|
|
364 ; rcall I2C_WaitforACK
|
|
|
365 ; movff i2c_temp2, SSPBUF ; Data Byte
|
|
|
366 ; rcall WaitMSSP
|
|
|
367 ; rcall I2C_WaitforACK
|
|
|
368 ; bsf SSPCON2,PEN ; Stop condition
|
|
|
369 ; rcall WaitMSSP
|
|
|
370 ; return
|
|
|
371 ;I2C_RX:
|
|
|
372 ; bcf PIR1,SSPIF
|
|
|
373 ; bsf SSPCON2,SEN ; Start condition
|
|
|
374 ; rcall WaitMSSP
|
|
|
375 ; movlw b'10010001' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
376 ; movwf SSPBUF ; control byte
|
|
|
377 ; rcall WaitMSSP
|
|
|
378 ; rcall I2C_WaitforACK
|
|
|
379 ; bsf SSPCON2, RCEN ; Enable recieve mode
|
|
|
380 ; rcall WaitMSSP
|
|
|
381 ; movff SSPBUF,i2c_temp2 ; Data Byte
|
|
|
382 ; bsf SSPCON2,ACKEN ; Master acknowlegde
|
|
|
383 ; rcall WaitMSSP
|
|
|
384 ; bsf SSPCON2,PEN ; Stop condition
|
|
|
385 ; rcall WaitMSSP
|
|
|
386 ; return |
