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annotate code_part1/OSTC_code_asm_part1/i2c_eeprom.asm @ 81:31fa973a70fd
Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
| author | JeanDo |
|---|---|
| date | Mon, 06 Dec 2010 18:05:39 +0100 |
| parents | 263348f83485 |
| children | 3e351e25f5d1 |
| rev | line source |
|---|---|
| 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 | |
|
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31fa973a70fd
Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
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73 #ifdef TESTING |
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Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
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74 ; When Simulating with MPLabSIM, there is no way to emulate external EEPROM... |
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31fa973a70fd
Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
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75 return |
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Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
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76 #endif |
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Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
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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 | |
| 91 write_external_eeprom_block: ; Writes a block of 64Byte (one page in external EEPROM without stop condition | |
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81
31fa973a70fd
Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
53
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changeset
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92 #ifdef TESTING |
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31fa973a70fd
Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
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changeset
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93 ; When Simulating with MPLabSIM, there is no way to emulate external EEPROM... |
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31fa973a70fd
Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
53
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changeset
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94 return |
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Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
53
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changeset
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95 #endif |
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Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
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96 |
| 0 | 97 btfsc eeprom_blockwrite ; Blockwrite continue? |
| 98 rcall I2CWRITE_BLOCK2 | |
| 99 btfss eeprom_blockwrite ; Blockwrite start? | |
| 100 rcall I2CWRITE_BLOCK | |
| 101 bsf eeprom_blockwrite ; After the start, do blockwriting for the next 63Bytes! | |
| 102 | |
| 103 movlw d'0' ; increase address | |
| 104 incf eeprom_address+0,F | |
| 105 addwfc eeprom_address+1,F | |
| 106 bcf eeprom_overflow | |
| 107 | |
| 108 btfss eeprom_address+1,7 ; at address 8000 | |
| 109 return ; no, return | |
| 110 | |
| 111 clrf eeprom_address+0 ; Clear eeprom address | |
| 112 clrf eeprom_address+1 | |
| 113 bsf eeprom_overflow ; and set overflow bit | |
| 114 return | |
| 115 I2CWRITE_BLOCK: | |
| 116 movwf ext_ee_temp1 ; Data byte in WREG | |
| 117 bsf SSPCON2,SEN ; Start condition | |
| 118 rcall WaitMSSP | |
| 119 movlw b'10100110' ; Bit0=0: WRITE, Bit0=1: READ | |
| 120 movwf SSPBUF ; control byte | |
| 121 rcall WaitMSSP | |
| 122 rcall I2C_WaitforACK | |
| 123 movff eeprom_address+1,SSPBUF ; High Address byte | |
| 124 rcall WaitMSSP | |
| 125 rcall I2C_WaitforACK | |
| 126 movff eeprom_address+0,SSPBUF ; Low Address byte | |
| 127 rcall WaitMSSP | |
| 128 rcall I2C_WaitforACK | |
| 129 I2CWRITE_BLOCK2: | |
| 130 movff ext_ee_temp1, SSPBUF ; Data Byte | |
| 131 rcall WaitMSSP | |
| 132 rcall I2C_WaitforACK | |
| 133 return | |
| 134 | |
| 135 | |
| 136 get_free_EEPROM_location: ; Searches 0xFD, 0xFD, 0xFE and sets Pointer to 0xFE | |
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31fa973a70fd
Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
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changeset
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137 |
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Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
53
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changeset
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138 #ifdef TESTING |
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Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
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139 ; In testing mode, find 0x100 (internal EEPROM) as the first free location... |
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31fa973a70fd
Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
53
diff
changeset
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140 clrf eeprom_address+0 ; Not found in entire EEPROM, set to address 0 |
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Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
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changeset
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141 movlw 0x1 |
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Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
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changeset
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142 movwf eeprom_address+1 |
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Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
53
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changeset
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143 return |
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31fa973a70fd
Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
53
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changeset
|
144 #endif |
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31fa973a70fd
Kludges to emulate inexisting devices when debugged with the MPLAB software SIMulator.
JeanDo
parents:
53
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changeset
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145 |
| 0 | 146 clrf ext_ee_temp1 ; low address counter |
| 147 clrf ext_ee_temp2 ; high address counter | |
| 148 bcf second_FD ; clear flags | |
| 149 bcf first_FD | |
| 150 get_free_EEPROM_location3: | |
| 151 bsf SSPCON2, PEN ; Stop condition | |
| 152 rcall WaitMSSP | |
| 153 bsf SSPCON2,SEN ; Start condition | |
| 154 rcall WaitMSSP | |
| 155 movlw b'10100110' ; Bit0=0: WRITE, Bit0=1: READ | |
| 156 movwf SSPBUF ; control byte | |
| 157 rcall WaitMSSP | |
| 158 btfsc SSPCON2,ACKSTAT | |
| 159 bra get_free_EEPROM_location3 ; EEPROM NOT acknowledged, retry! | |
| 160 | |
| 161 movff ext_ee_temp2,SSPBUF ; High Address byte | |
| 162 rcall WaitMSSP | |
| 163 rcall I2C_WaitforACK | |
| 164 movff ext_ee_temp1,SSPBUF ; Low Address byte | |
| 165 rcall WaitMSSP | |
| 166 rcall I2C_WaitforACK | |
| 167 | |
| 168 bsf SSPCON2,RSEN ; Start condition | |
| 169 rcall WaitMSSP | |
| 170 movlw b'10100111' ; Bit0=0: WRITE, Bit0=1: READ | |
| 171 movwf SSPBUF ; control byte | |
| 172 rcall WaitMSSP | |
| 173 rcall I2C_WaitforACK | |
| 174 | |
| 175 get_free_EEPROM_location2: | |
| 176 bsf SSPCON2, RCEN ; Enable recieve mode | |
| 177 rcall WaitMSSP | |
| 178 btfsc first_FD | |
| 179 bra test_2nd_FD | |
| 180 bsf first_FD ; found first 0xFD? | |
| 181 movlw 0xFD | |
| 182 cpfseq SSPBUF | |
| 183 bcf first_FD ; No | |
| 184 bra get_free_EEPROM_location2c | |
| 185 | |
| 186 test_2nd_FD: | |
| 187 btfsc second_FD | |
| 188 bra test_FE | |
| 189 bsf second_FD ; found second 0xFD? | |
| 190 movlw 0xFD | |
| 191 cpfseq SSPBUF | |
| 192 bra get_free_EEPROM_location2b ;No, clear both flags | |
| 193 bra get_free_EEPROM_location2c | |
| 194 test_FE: | |
| 195 movlw 0xFE ; found the final 0xFE? | |
| 196 cpfseq SSPBUF | |
| 197 bra get_free_EEPROM_location2b ;No, clear both flags | |
| 198 movff ext_ee_temp1,eeprom_address+0 ;Yes, copy ext_ee_temp1->eeprom_address+0 and | |
| 199 movff ext_ee_temp2,eeprom_address+1 ;ext_ee_temp2->eeprom_address+1 | |
| 200 bra get_free_EEPROM_location4 ; Done. | |
| 201 | |
| 202 get_free_EEPROM_location2b: | |
| 203 bcf second_FD ; clear both flags! | |
| 204 bcf first_FD | |
| 205 get_free_EEPROM_location2c: | |
| 206 movlw d'1' ; and increase search address | |
| 207 addwf ext_ee_temp1,F | |
| 208 movlw d'0' | |
| 209 addwfc ext_ee_temp2,F | |
| 210 | |
| 42 | 211 btfsc ext_ee_temp2,7 ; 0x8000 reached? |
| 0 | 212 bra get_free_EEPROM_location3b ; yes |
| 213 | |
| 214 bsf SSPCON2, ACKEN ; no, send Ack | |
| 215 rcall WaitMSSP | |
| 216 bra get_free_EEPROM_location2 ; and continue search | |
| 217 get_free_EEPROM_location3b: | |
| 218 clrf eeprom_address+0 ; Not found in entire EEPROM, set to address 0 | |
| 219 clrf eeprom_address+1 | |
| 220 get_free_EEPROM_location4: | |
| 221 bsf SSPCON2, PEN ; Stop | |
| 222 rcall WaitMSSP | |
| 223 | |
| 224 bcf second_FD ; clear flags | |
| 225 bcf first_FD | |
| 226 return ; return | |
| 227 | |
| 228 | |
| 229 I2CREAD: | |
| 230 bsf SSPCON2, PEN ; Stop | |
| 231 rcall WaitMSSP | |
| 232 bsf SSPCON2,SEN ; Start condition | |
| 233 rcall WaitMSSP | |
| 234 movlw b'10100110' ; Bit0=0: WRITE, Bit0=1: READ | |
| 235 movwf SSPBUF ; control byte | |
| 236 rcall WaitMSSP | |
| 237 btfsc SSPCON2,ACKSTAT | |
| 238 bra I2CREAD ; EEPROM NOT acknowledged, retry! | |
| 239 movff eeprom_address+1,SSPBUF ; High Address byte | |
| 240 rcall WaitMSSP | |
| 241 rcall I2C_WaitforACK | |
| 242 movff eeprom_address+0,SSPBUF ; Low Address byte | |
| 243 rcall WaitMSSP | |
| 244 rcall I2C_WaitforACK | |
| 245 | |
| 246 bsf SSPCON2,RSEN ; Start condition | |
| 247 rcall WaitMSSP | |
| 248 movlw b'10100111' ; Bit0=0: WRITE, Bit0=1: READ | |
| 249 movwf SSPBUF ; control byte | |
| 250 rcall WaitMSSP | |
| 251 rcall I2C_WaitforACK | |
| 252 | |
| 253 bsf SSPCON2, RCEN ; Enable recieve mode | |
| 254 rcall WaitMSSP | |
| 255 movf SSPBUF,W ; copy read byte into WREG | |
| 256 bsf SSPCON2, PEN ; Stop | |
| 257 rcall WaitMSSP | |
| 258 return | |
| 259 | |
| 260 I2CREAD2: ; same as I2CREAD but with automatic address increase | |
| 261 rcall I2CREAD | |
| 262 movlw d'1' | |
| 263 addwf eeprom_address+0,F | |
| 264 movlw d'0' | |
| 265 addwfc eeprom_address+1,F | |
| 266 bcf eeprom_overflow | |
| 267 btfss eeprom_address+1,7 ; at 0x8000? | |
| 268 return ; no, return | |
| 269 | |
| 270 clrf eeprom_address+0 ; Yes, clear address | |
| 271 clrf eeprom_address+1 | |
| 272 bsf eeprom_overflow ; and set overflow bit | |
| 273 return | |
| 274 | |
| 275 I2CWRITE: | |
| 276 movwf ext_ee_temp1 ; Data byte | |
| 277 bsf SSPCON2,SEN ; Start condition | |
| 278 rcall WaitMSSP | |
| 279 movlw b'10100110' ; Bit0=0: WRITE, Bit0=1: READ | |
| 280 movwf SSPBUF ; control byte | |
| 281 rcall WaitMSSP | |
| 282 rcall I2C_WaitforACK | |
| 283 movff eeprom_address+1,SSPBUF ; High Address byte | |
| 284 rcall WaitMSSP | |
| 285 rcall I2C_WaitforACK | |
| 286 movff eeprom_address+0,SSPBUF ; Low Address byte | |
| 287 rcall WaitMSSP | |
| 288 rcall I2C_WaitforACK | |
| 289 movff ext_ee_temp1, SSPBUF ; Data Byte | |
| 290 rcall WaitMSSP | |
| 291 rcall I2C_WaitforACK | |
| 292 bsf SSPCON2,PEN ; Stop condition | |
| 293 rcall WaitMSSP | |
| 294 WAITMS d'6' ; Write delay | |
| 295 return | |
| 296 | |
| 297 I2C_WaitforACK: | |
| 298 btfsc SSPCON2,ACKSTAT ; checks for ACK bit from slave | |
| 299 rcall I2CFail | |
| 300 return | |
| 301 | |
| 302 I2CFail: | |
| 303 ostc_debug 'M' ; Sends debug-information to screen if debugmode active | |
| 21 | 304 bsf LED_red |
| 0 | 305 rcall I2CReset ; I2C Reset |
| 306 bcf PIR1,SSPIF | |
| 307 clrf i2c_temp | |
| 308 return | |
| 309 | |
| 310 WaitMSSP: | |
| 311 decfsz i2c_temp,F ; check for timeout during I2C action | |
| 312 bra WaitMSSP2 | |
| 313 bra I2CFail ; timeout occured | |
| 314 WaitMSSP2: | |
| 315 btfss PIR1,SSPIF | |
| 316 bra WaitMSSP | |
| 317 clrf i2c_temp | |
| 318 bcf PIR1,SSPIF | |
| 319 return | |
| 320 | |
| 321 I2CReset: ; Something went wrong (Slave holds SDA low?) | |
| 322 clrf SSPCON1 ; wake-up slave and reset entire module | |
| 323 ostc_debug 'N' ; Sends debug-information to screen if debugmode active | |
| 324 clrf SSPCON2 | |
| 325 clrf SSPSTAT | |
| 326 bcf TRISC,3 ; SCL OUTPUT | |
| 327 bsf TRISC,4 ; SDA Input | |
| 328 bcf PORTC,3 | |
| 329 movlw d'9' | |
| 330 movwf i2c_temp ; clock-out 9 clock cycles manually | |
| 331 I2CReset_1: | |
| 332 bsf PORTC,3 ; SCL=1 | |
| 333 nop | |
| 334 btfsc PORTC,4 ; SDA=1? | |
| 335 bra I2CReset_2 ; =1, SDA has been released from slave | |
| 336 bcf PORTC,3 ; SCL=0 | |
| 337 bcf PORTC,3 | |
| 338 decfsz i2c_temp,F | |
| 339 bra I2CReset_1 ; check for nine clock cycles | |
| 340 I2CReset_2: | |
| 341 bsf TRISC,3 ; SCL Input | |
| 342 clrf SSPCON1 ; set I²C Mode | |
| 343 WAITMS d'10' ; Reset-Timeout for I2C devices | |
| 344 movlw b'00000000' | |
| 345 movwf SSPSTAT | |
| 346 movlw b'00101000' | |
| 347 movwf SSPCON1 | |
| 348 movlw b'00000000' | |
| 349 movwf SSPCON2 | |
| 350 movlw d'8' ; 400kHz I2C clock @ 16MHz Fcy | |
| 351 movwf SSPADD | |
| 21 | 352 bcf LED_red |
| 0 | 353 ostc_debug 'O' ; Sends debug-information to screen if debugmode active |
| 354 return | |
| 53 | 355 |
| 356 ;I2C_TX: | |
| 357 ; movwf i2c_temp2 ; Data byte | |
| 358 ; bsf SSPCON2,SEN ; Start condition | |
| 359 ; rcall WaitMSSP | |
| 360 ; movlw b'10010000' ; Bit0=0: WRITE, Bit0=1: READ | |
| 361 ; movwf SSPBUF ; control byte | |
| 362 ; rcall WaitMSSP | |
| 363 ; rcall I2C_WaitforACK | |
| 364 ; movff i2c_temp2, SSPBUF ; Data Byte | |
| 365 ; rcall WaitMSSP | |
| 366 ; rcall I2C_WaitforACK | |
| 367 ; bsf SSPCON2,PEN ; Stop condition | |
| 368 ; rcall WaitMSSP | |
| 369 ; return | |
| 370 ;I2C_RX: | |
| 371 ; bcf PIR1,SSPIF | |
| 372 ; bsf SSPCON2,SEN ; Start condition | |
| 373 ; rcall WaitMSSP | |
| 374 ; movlw b'10010001' ; Bit0=0: WRITE, Bit0=1: READ | |
| 375 ; movwf SSPBUF ; control byte | |
| 376 ; rcall WaitMSSP | |
| 377 ; rcall I2C_WaitforACK | |
| 378 ; bsf SSPCON2, RCEN ; Enable recieve mode | |
| 379 ; rcall WaitMSSP | |
| 380 ; movff SSPBUF,i2c_temp2 ; Data Byte | |
| 381 ; bsf SSPCON2,ACKEN ; Master acknowlegde | |
| 382 ; rcall WaitMSSP | |
| 383 ; bsf SSPCON2,PEN ; Stop condition | |
| 384 ; rcall WaitMSSP | |
| 385 ; return |