|
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
|
|
|
73 rcall I2CWRITE ; writes WREG into EEPROM@eeprom_address
|
|
|
74 movlw d'1' ; increase address
|
|
|
75 addwf eeprom_address+0,F
|
|
|
76 movlw d'0'
|
|
|
77 addwfc eeprom_address+1,F
|
|
|
78 bcf eeprom_overflow
|
|
|
79 btfss eeprom_address+1,7 ; at address 8000?
|
|
|
80 return ; no, return
|
|
|
81
|
|
|
82 clrf eeprom_address+0 ; Clear eeprom address
|
|
|
83 clrf eeprom_address+1
|
|
|
84 bsf eeprom_overflow ; and set overflow bit
|
|
|
85 return
|
|
|
86 write_external_eeprom_block: ; Writes a block of 64Byte (one page in external EEPROM without stop condition
|
|
|
87 btfsc eeprom_blockwrite ; Blockwrite continue?
|
|
|
88 rcall I2CWRITE_BLOCK2
|
|
|
89 btfss eeprom_blockwrite ; Blockwrite start?
|
|
|
90 rcall I2CWRITE_BLOCK
|
|
|
91 bsf eeprom_blockwrite ; After the start, do blockwriting for the next 63Bytes!
|
|
|
92
|
|
|
93 movlw d'0' ; increase address
|
|
|
94 incf eeprom_address+0,F
|
|
|
95 addwfc eeprom_address+1,F
|
|
|
96 bcf eeprom_overflow
|
|
|
97
|
|
|
98 btfss eeprom_address+1,7 ; at address 8000
|
|
|
99 return ; no, return
|
|
|
100
|
|
|
101 clrf eeprom_address+0 ; Clear eeprom address
|
|
|
102 clrf eeprom_address+1
|
|
|
103 bsf eeprom_overflow ; and set overflow bit
|
|
|
104 return
|
|
|
105 I2CWRITE_BLOCK:
|
|
|
106 movwf ext_ee_temp1 ; Data byte in WREG
|
|
|
107 bsf SSPCON2,SEN ; Start condition
|
|
|
108 rcall WaitMSSP
|
|
|
109 movlw b'10100110' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
110 movwf SSPBUF ; control byte
|
|
|
111 rcall WaitMSSP
|
|
|
112 rcall I2C_WaitforACK
|
|
|
113 movff eeprom_address+1,SSPBUF ; High Address byte
|
|
|
114 rcall WaitMSSP
|
|
|
115 rcall I2C_WaitforACK
|
|
|
116 movff eeprom_address+0,SSPBUF ; Low Address byte
|
|
|
117 rcall WaitMSSP
|
|
|
118 rcall I2C_WaitforACK
|
|
|
119 I2CWRITE_BLOCK2:
|
|
|
120 movff ext_ee_temp1, SSPBUF ; Data Byte
|
|
|
121 rcall WaitMSSP
|
|
|
122 rcall I2C_WaitforACK
|
|
|
123 return
|
|
|
124
|
|
|
125
|
|
|
126 get_free_EEPROM_location: ; Searches 0xFD, 0xFD, 0xFE and sets Pointer to 0xFE
|
|
|
127 clrf ext_ee_temp1 ; low address counter
|
|
|
128 clrf ext_ee_temp2 ; high address counter
|
|
|
129 bcf second_FD ; clear flags
|
|
|
130 bcf first_FD
|
|
|
131 get_free_EEPROM_location3:
|
|
|
132 bsf SSPCON2, PEN ; Stop condition
|
|
|
133 rcall WaitMSSP
|
|
|
134 bsf SSPCON2,SEN ; Start condition
|
|
|
135 rcall WaitMSSP
|
|
|
136 movlw b'10100110' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
137 movwf SSPBUF ; control byte
|
|
|
138 rcall WaitMSSP
|
|
|
139 btfsc SSPCON2,ACKSTAT
|
|
|
140 bra get_free_EEPROM_location3 ; EEPROM NOT acknowledged, retry!
|
|
|
141
|
|
|
142 movff ext_ee_temp2,SSPBUF ; High Address byte
|
|
|
143 rcall WaitMSSP
|
|
|
144 rcall I2C_WaitforACK
|
|
|
145 movff ext_ee_temp1,SSPBUF ; Low Address byte
|
|
|
146 rcall WaitMSSP
|
|
|
147 rcall I2C_WaitforACK
|
|
|
148
|
|
|
149 bsf SSPCON2,RSEN ; Start condition
|
|
|
150 rcall WaitMSSP
|
|
|
151 movlw b'10100111' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
152 movwf SSPBUF ; control byte
|
|
|
153 rcall WaitMSSP
|
|
|
154 rcall I2C_WaitforACK
|
|
|
155
|
|
|
156 get_free_EEPROM_location2:
|
|
|
157 bsf SSPCON2, RCEN ; Enable recieve mode
|
|
|
158 rcall WaitMSSP
|
|
|
159 btfsc first_FD
|
|
|
160 bra test_2nd_FD
|
|
|
161 bsf first_FD ; found first 0xFD?
|
|
|
162 movlw 0xFD
|
|
|
163 cpfseq SSPBUF
|
|
|
164 bcf first_FD ; No
|
|
|
165 bra get_free_EEPROM_location2c
|
|
|
166
|
|
|
167 test_2nd_FD:
|
|
|
168 btfsc second_FD
|
|
|
169 bra test_FE
|
|
|
170 bsf second_FD ; found second 0xFD?
|
|
|
171 movlw 0xFD
|
|
|
172 cpfseq SSPBUF
|
|
|
173 bra get_free_EEPROM_location2b ;No, clear both flags
|
|
|
174 bra get_free_EEPROM_location2c
|
|
|
175 test_FE:
|
|
|
176 movlw 0xFE ; found the final 0xFE?
|
|
|
177 cpfseq SSPBUF
|
|
|
178 bra get_free_EEPROM_location2b ;No, clear both flags
|
|
|
179 movff ext_ee_temp1,eeprom_address+0 ;Yes, copy ext_ee_temp1->eeprom_address+0 and
|
|
|
180 movff ext_ee_temp2,eeprom_address+1 ;ext_ee_temp2->eeprom_address+1
|
|
|
181 bra get_free_EEPROM_location4 ; Done.
|
|
|
182
|
|
|
183 get_free_EEPROM_location2b:
|
|
|
184 bcf second_FD ; clear both flags!
|
|
|
185 bcf first_FD
|
|
|
186 get_free_EEPROM_location2c:
|
|
|
187 movlw d'1' ; and increase search address
|
|
|
188 addwf ext_ee_temp1,F
|
|
|
189 movlw d'0'
|
|
|
190 addwfc ext_ee_temp2,F
|
|
|
191
|
|
42
|
192 btfsc ext_ee_temp2,7 ; 0x8000 reached?
|
|
0
|
193 bra get_free_EEPROM_location3b ; yes
|
|
|
194
|
|
|
195 bsf SSPCON2, ACKEN ; no, send Ack
|
|
|
196 rcall WaitMSSP
|
|
|
197 bra get_free_EEPROM_location2 ; and continue search
|
|
|
198 get_free_EEPROM_location3b:
|
|
|
199 clrf eeprom_address+0 ; Not found in entire EEPROM, set to address 0
|
|
|
200 clrf eeprom_address+1
|
|
|
201 get_free_EEPROM_location4:
|
|
|
202 bsf SSPCON2, PEN ; Stop
|
|
|
203 rcall WaitMSSP
|
|
|
204
|
|
|
205 bcf second_FD ; clear flags
|
|
|
206 bcf first_FD
|
|
|
207 return ; return
|
|
|
208
|
|
|
209
|
|
|
210 I2CREAD:
|
|
|
211 bsf SSPCON2, PEN ; Stop
|
|
|
212 rcall WaitMSSP
|
|
|
213 bsf SSPCON2,SEN ; Start condition
|
|
|
214 rcall WaitMSSP
|
|
|
215 movlw b'10100110' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
216 movwf SSPBUF ; control byte
|
|
|
217 rcall WaitMSSP
|
|
|
218 btfsc SSPCON2,ACKSTAT
|
|
|
219 bra I2CREAD ; EEPROM NOT acknowledged, retry!
|
|
|
220 movff eeprom_address+1,SSPBUF ; High Address byte
|
|
|
221 rcall WaitMSSP
|
|
|
222 rcall I2C_WaitforACK
|
|
|
223 movff eeprom_address+0,SSPBUF ; Low Address byte
|
|
|
224 rcall WaitMSSP
|
|
|
225 rcall I2C_WaitforACK
|
|
|
226
|
|
|
227 bsf SSPCON2,RSEN ; Start condition
|
|
|
228 rcall WaitMSSP
|
|
|
229 movlw b'10100111' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
230 movwf SSPBUF ; control byte
|
|
|
231 rcall WaitMSSP
|
|
|
232 rcall I2C_WaitforACK
|
|
|
233
|
|
|
234 bsf SSPCON2, RCEN ; Enable recieve mode
|
|
|
235 rcall WaitMSSP
|
|
|
236 movf SSPBUF,W ; copy read byte into WREG
|
|
|
237 bsf SSPCON2, PEN ; Stop
|
|
|
238 rcall WaitMSSP
|
|
|
239 return
|
|
|
240
|
|
|
241 I2CREAD2: ; same as I2CREAD but with automatic address increase
|
|
|
242 rcall I2CREAD
|
|
|
243 movlw d'1'
|
|
|
244 addwf eeprom_address+0,F
|
|
|
245 movlw d'0'
|
|
|
246 addwfc eeprom_address+1,F
|
|
|
247 bcf eeprom_overflow
|
|
|
248 btfss eeprom_address+1,7 ; at 0x8000?
|
|
|
249 return ; no, return
|
|
|
250
|
|
|
251 clrf eeprom_address+0 ; Yes, clear address
|
|
|
252 clrf eeprom_address+1
|
|
|
253 bsf eeprom_overflow ; and set overflow bit
|
|
|
254 return
|
|
|
255
|
|
|
256 I2CWRITE:
|
|
|
257 movwf ext_ee_temp1 ; Data byte
|
|
|
258 bsf SSPCON2,SEN ; Start condition
|
|
|
259 rcall WaitMSSP
|
|
|
260 movlw b'10100110' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
261 movwf SSPBUF ; control byte
|
|
|
262 rcall WaitMSSP
|
|
|
263 rcall I2C_WaitforACK
|
|
|
264 movff eeprom_address+1,SSPBUF ; High Address byte
|
|
|
265 rcall WaitMSSP
|
|
|
266 rcall I2C_WaitforACK
|
|
|
267 movff eeprom_address+0,SSPBUF ; Low Address byte
|
|
|
268 rcall WaitMSSP
|
|
|
269 rcall I2C_WaitforACK
|
|
|
270 movff ext_ee_temp1, SSPBUF ; Data Byte
|
|
|
271 rcall WaitMSSP
|
|
|
272 rcall I2C_WaitforACK
|
|
|
273 bsf SSPCON2,PEN ; Stop condition
|
|
|
274 rcall WaitMSSP
|
|
|
275 WAITMS d'6' ; Write delay
|
|
|
276 return
|
|
|
277
|
|
|
278 I2C_WaitforACK:
|
|
|
279 btfsc SSPCON2,ACKSTAT ; checks for ACK bit from slave
|
|
|
280 rcall I2CFail
|
|
|
281 return
|
|
|
282
|
|
|
283 I2CFail:
|
|
|
284 ostc_debug 'M' ; Sends debug-information to screen if debugmode active
|
|
21
|
285 bsf LED_red
|
|
0
|
286 rcall I2CReset ; I2C Reset
|
|
|
287 bcf PIR1,SSPIF
|
|
|
288 clrf i2c_temp
|
|
|
289 return
|
|
|
290
|
|
|
291 WaitMSSP:
|
|
|
292 decfsz i2c_temp,F ; check for timeout during I2C action
|
|
|
293 bra WaitMSSP2
|
|
|
294 bra I2CFail ; timeout occured
|
|
|
295 WaitMSSP2:
|
|
|
296 btfss PIR1,SSPIF
|
|
|
297 bra WaitMSSP
|
|
|
298 clrf i2c_temp
|
|
|
299 bcf PIR1,SSPIF
|
|
|
300 return
|
|
|
301
|
|
|
302 I2CReset: ; Something went wrong (Slave holds SDA low?)
|
|
|
303 clrf SSPCON1 ; wake-up slave and reset entire module
|
|
|
304 ostc_debug 'N' ; Sends debug-information to screen if debugmode active
|
|
|
305 clrf SSPCON2
|
|
|
306 clrf SSPSTAT
|
|
|
307 bcf TRISC,3 ; SCL OUTPUT
|
|
|
308 bsf TRISC,4 ; SDA Input
|
|
|
309 bcf PORTC,3
|
|
|
310 movlw d'9'
|
|
|
311 movwf i2c_temp ; clock-out 9 clock cycles manually
|
|
|
312 I2CReset_1:
|
|
|
313 bsf PORTC,3 ; SCL=1
|
|
|
314 nop
|
|
|
315 btfsc PORTC,4 ; SDA=1?
|
|
|
316 bra I2CReset_2 ; =1, SDA has been released from slave
|
|
|
317 bcf PORTC,3 ; SCL=0
|
|
|
318 bcf PORTC,3
|
|
|
319 decfsz i2c_temp,F
|
|
|
320 bra I2CReset_1 ; check for nine clock cycles
|
|
|
321 I2CReset_2:
|
|
|
322 bsf TRISC,3 ; SCL Input
|
|
|
323 clrf SSPCON1 ; set I²C Mode
|
|
|
324 WAITMS d'10' ; Reset-Timeout for I2C devices
|
|
|
325 movlw b'00000000'
|
|
|
326 movwf SSPSTAT
|
|
|
327 movlw b'00101000'
|
|
|
328 movwf SSPCON1
|
|
|
329 movlw b'00000000'
|
|
|
330 movwf SSPCON2
|
|
|
331 movlw d'8' ; 400kHz I2C clock @ 16MHz Fcy
|
|
|
332 movwf SSPADD
|
|
21
|
333 bcf LED_red
|
|
0
|
334 ostc_debug 'O' ; Sends debug-information to screen if debugmode active
|
|
|
335 return
|
|
53
|
336
|
|
|
337 ;I2C_TX:
|
|
|
338 ; movwf i2c_temp2 ; Data byte
|
|
|
339 ; bsf SSPCON2,SEN ; Start condition
|
|
|
340 ; rcall WaitMSSP
|
|
|
341 ; movlw b'10010000' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
342 ; movwf SSPBUF ; control byte
|
|
|
343 ; rcall WaitMSSP
|
|
|
344 ; rcall I2C_WaitforACK
|
|
|
345 ; movff i2c_temp2, SSPBUF ; Data Byte
|
|
|
346 ; rcall WaitMSSP
|
|
|
347 ; rcall I2C_WaitforACK
|
|
|
348 ; bsf SSPCON2,PEN ; Stop condition
|
|
|
349 ; rcall WaitMSSP
|
|
|
350 ; return
|
|
|
351 ;I2C_RX:
|
|
|
352 ; bcf PIR1,SSPIF
|
|
|
353 ; bsf SSPCON2,SEN ; Start condition
|
|
|
354 ; rcall WaitMSSP
|
|
|
355 ; movlw b'10010001' ; Bit0=0: WRITE, Bit0=1: READ
|
|
|
356 ; movwf SSPBUF ; control byte
|
|
|
357 ; rcall WaitMSSP
|
|
|
358 ; rcall I2C_WaitforACK
|
|
|
359 ; bsf SSPCON2, RCEN ; Enable recieve mode
|
|
|
360 ; rcall WaitMSSP
|
|
|
361 ; movff SSPBUF,i2c_temp2 ; Data Byte
|
|
|
362 ; bsf SSPCON2,ACKEN ; Master acknowlegde
|
|
|
363 ; rcall WaitMSSP
|
|
|
364 ; bsf SSPCON2,PEN ; Stop condition
|
|
|
365 ; rcall WaitMSSP
|
|
|
366 ; return |
