akc6955.c

   1 /*
   2  * OpenI2CRADIO
   3  * RADIO CHIP AKC6955 Handler
   4  * Copyright (C) 2013-06-10 K.Ohta <whatisthis.sowhat ai gmail.com>
   5  * License: GPL2+LE
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2,
  10  *  or (at your option) any later version.
  11  *  This library / program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  14  *  See the GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this library; see the file COPYING. If not, write to the
  18  *  Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
  19  *  MA 02110-1301, USA.
  20  *
  21  *  As a special exception, if you link this(includeed from sdcc) library
  22  *  with other files, some of which are compiled with SDCC,
  23  *  to produce an executable, this library does not by itself cause
  24  *  the resulting executable to be covered by the GNU General Public License.
  25  *  This exception does not however invalidate any other reasons why
  26  *  the executable file might be covered by the GNU General Public License.
  27  */
  28
  29 #include <stdarg.h>
  30 #include <stdio.h>
  31 #ifdef __SDCC
  32 #include <delay.h>
  33 #else
  34 #include <xc.h>
  35 #endif
  36 #include <string.h>
  37 #include "akc6955.h"
  38 #include "i2c_io.h"
  39 #include "idle.h"
  40 #include "power.h"
  41 #include "commondef.h"
  42 #include "menu.h"
  43
  44 void akc6955_writecmd(unsigned char reg, unsigned char data)
  45 {
  46 #ifdef __SDCC
  47     i2c_open(I2C_MASTER, I2C_SLEW_ON, 5);
  48     I2C_START();
  49     i2c_writechar(0x20);
  50     i2c_writechar(reg);
  51     i2c_writechar(data);
  52     I2C_STOP();
  53     i2c_close();
  54     delay100tcy(2);
  55 #else
  56     OpenI2C(MASTER, SLEW_ON);
  57     SSPADD = 0x5;
  58 //    IdleI2C();
  59     StartI2C();
  60     WriteI2C(0x20);
  61     //delay1ktcy(8);
  62     WriteI2C(reg);
  63     //delay1ktcy(8);
  64     WriteI2C(data);
  65     //delay1ktcy(8);
  66     StopI2C();
  67  //   delay1ktcy(8);
  68     CloseI2C();
  69 #endif  //    i2c_idle();
  70 }
  71
  72 unsigned char akc6955_readcmd(unsigned char reg)
  73 {
  74     unsigned char c;
  75     //    OPENASMASTER();
  76 #ifdef __SDCC
  77     i2c_open(I2C_MASTER, I2C_SLEW_ON, 5);
  78     I2C_START();
  79     i2c_writechar(0x20);
  80     i2c_writechar(reg);
  81     I2C_STOP();
  82     delay100tcy(2);
  83     I2C_START();
  84     i2c_writechar(0x21);
  85     c = i2c_readchar();
  86     I2C_ACK();
  87     I2C_STOP();
  88     i2c_close();
  89 #else
  90     OpenI2C(MASTER, SLEW_ON);
  91     SSPADD = 0x5;
  92 //    IdleI2C();
  93     StartI2C();
  94     WriteI2C(0x20);
  95   //  delay1ktcy(8);
  96     WriteI2C(reg);
  97   //  delay1ktcy(8);
  98     StopI2C();
  99     __delay_us(13);
 100     StartI2C();
 101     WriteI2C(0x21);
 102   //  delay1ktcy(8);
 103     c = ReadI2C();
 104     AckI2C();
 105     StopI2C();
 106  //   delay1ktcy(8);
 107     CloseI2C();
 108 #endif
 109     //    CLOSEASMASTER();
 110
 111     return c;
 112 }
 113
 114 void akc6955_chg_fm(unsigned char f, unsigned int freq)
 115 {
 116     __bitops_t b;
 117     b.byte = akc6955_readcmd(AKC6955_POWER);
 118     b.b6 = 0;
 119     if(f != 0){
 120         b.b6 = 1;
 121         akc6955_set_fmband(fmband);
 122         akc6955_writecmd(AKC6955_POWER, b.byte);
 123         akc6955_set_freq(freq);
 124         return;
 125     }
 126     akc6955_writecmd(AKC6955_POWER, b.byte);
 127     akc6955_set_amband(amband);
 128     akc6955_set_freq(freq);
 129
 130 }
 131
 132 unsigned char akc6955_get_fm(void)
 133 {
 134     __bitops_t b;
 135     b.byte = akc6955_readcmd(AKC6955_POWER);
 136     if(b.b6){
 137         return 0xff;
 138     }
 139     return 0;
 140 }
 141
 142
 143 void akc6955_set_amband(unsigned char band)
 144 {
 145     unsigned char b;
 146     unsigned char c;
 147
 148     c = RFAMP_SW;
 149     if((band < AKC6955_BAND_SW1) || (band == AKC6955_BAND_MW4)) {
 150         c = RFAMP_MWLW;
 151     }
 152     rfamp_power(c);
 153     b = akc6955_readcmd(AKC6955_BAND);
 154     b &= 0x07; // extract FM
 155     b = b | ((band & 0x1f) << 3);
 156     akc6955_writecmd(AKC6955_BAND, b);
 157     akc6955_do_tune();
 158 }
 159
 160 void akc6955_set_fmband(unsigned char band)
 161 {
 162     unsigned char b;
 163     rfamp_power(RFAMP_FM);
 164     b = akc6955_readcmd(AKC6955_BAND);
 165     b &= 0xf8; // extract AM
 166     b = b | (band & 0x07);
 167     akc6955_writecmd(AKC6955_BAND, b);
 168     akc6955_do_tune();
 169 }
 170
 171 unsigned char akc6955_get_band(void)
 172 {
 173     return akc6955_readcmd(AKC6955_BAND);
 174 }
 175
 176
 177 void akc6955_set_power(unsigned char on)
 178 {
 179     __bitops_t b;
 180     b.byte = akc6955_readcmd(AKC6955_POWER);
 181     b.b7 = 0;
 182     if(on != 0){
 183         b.b7 = 1;
 184     }
 185     akc6955_writecmd(AKC6955_POWER, b.byte);
 186 }
 187
 188 void akc6955_do_tune(void)
 189 {
 190     __bitops_t b;
 191     b.byte = akc6955_readcmd(AKC6955_POWER);
 192     b.b5 = 0; // Tun = '0'
 193     b.b4 = 0; // Force abort scan.
 194     akc6955_writecmd(AKC6955_POWER, b.byte);
 195     idle_time_ms(1);
 196     // Need sleep?-> Need! this sequence re                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     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 197     b.b5= 1; // Tun = '1'
 198     akc6955_writecmd(AKC6955_POWER, b.byte);
 199     idle_time_ms(1);
 200     b.b5 = 0;
 201     akc6955_writecmd(AKC6955_POWER, b.byte);
 202     idle_time_ms(8);
 203 }
 204
 205 unsigned char akc6955_tune(void)
 206 {
 207     __bitops_t b;
 208     b.byte = akc6955_readcmd(AKC6955_RCH_HI);
 209     if(b.b5) {
 210         return 0xff;
 211     }
 212     return 0;
 213 }
 214
 215
 216 void akc6955_mode3k(unsigned char flag)
 217 {
 218     __bitops_t b;
 219     b.byte = akc6955_readcmd(AKC6955_CH_HI);
 220     b.b5 = 0;
 221     if(flag != 0){
 222         b.b5 = 1;
 223     }
 224     akc6955_writecmd(AKC6955_CH_HI, b.byte);
 225     akc6955_do_tune();
 226     _AKC6955_WAIT_62_5MS();
 227 }
 228
 229 void akc6955_set_tune(unsigned char mode_3k, unsigned int ch)
 230 {
 231     unsigned char band;
 232     __bitops_t f;
 233     __bitops_t b;
 234     unsigned int i = ch;
 235     unsigned char comp;
 236
 237     do { // Wait for before completed
 238         comp = akc6955_chk_donescan();
 239         idle_time_35ms();
 240     } while(comp == 0x00);
 241     f.byte = akc6955_readcmd(AKC6955_POWER);
 242     band = 0;
 243     if(!f.b6){
 244         akc6955_get_amband(band);
 245     }
 246
 247     if(band == AKC6955_BAND_MW2){
 248         // BAND=AM && MW2
 249         i = ch / 3; // On MW2, Channnel must be multiple of 3.
 250         i = i * 3; // i = (i/3) * 3
 251     }
 252     if(i > 0x1fff) i = 0x1fff;
 253     //i = ch & 0x1fff;
 254
 255     b.byte = i & 0xff;
 256     akc6955_writecmd(AKC6955_CH_LO, b.byte);
 257
 258     b.byte = i >> 8;
 259     b.b6 = 1;
 260     if(mode_3k != 0){
 261         b.b5 = 1; // Mode 3K ON
 262     }
 263     akc6955_writecmd(AKC6955_CH_HI, b.byte);
 264
 265     akc6955_do_tune();
 266 }
 267
 268 void akc6955_do_scan(unsigned char up)
 269 {
 270     __bitops_t b;
 271  //   akc6955_do_tune();
 272     b.byte = akc6955_readcmd(AKC6955_POWER);
 273     b.b3 = 0;
 274     b.b4 = 0;
 275     b.b5 = 0;
 276     akc6955_writecmd(AKC6955_POWER, b.byte);
 277     b.b5 = 1; // Tune 0->1.
 278     idle_time_35ms();
 279     akc6955_writecmd(AKC6955_POWER, b.byte);
 280     idle_time_35ms();
 281     if(up != 0) {
 282         b.b3= 1;
 283     }
 284     b.b4 = 1;
 285     akc6955_writecmd(AKC6955_POWER, b.byte); // Raise seek bit to '1'.
 286 }
 287
 288 void akc6955_abort_scan(void)
 289 {
 290     unsigned char b;
 291     b = akc6955_readcmd(AKC6955_POWER);
 292     b &= 0xef;
 293     akc6955_writecmd(AKC6955_POWER, b); // Falldown seek bit to '0'.
 294 }
 295
 296 void akc6955_set_scanrate_fm(unsigned char rate)
 297 {
 298     unsigned char c;
 299     c = akc6955_readcmd(AKC6955_SPACE);
 300     c = (c & 0xcf) | ((rate & 0x03) << 4);
 301     akc6955_writecmd(AKC6955_SPACE, c);
 302 }
 303
 304 unsigned char akc6955_chk_donescan(void)
 305 {
 306     __bitops_t b;
 307     b.byte = akc6955_readcmd(AKC6955_RCH_HI);
 308     if(b.b6){
 309         return 0xff;
 310     }
 311     return 0;
 312 }
 313
 314 unsigned int akc6955_get_channel(void)
 315 {
 316     unsigned char h, l;
 317     unsigned int u;
 318     l = akc6955_readcmd(AKC6955_RCH_LO) ;
 319     h = akc6955_readcmd(AKC6955_RCH_HI) & 0x1f;
 320     u = (h << 8) | l;
 321     return u;
 322 }
 323
 324 /*
 325  * Get AM/FM Frequency: ret = KHz at AM, 10KHz @FM.
 326  */
 327 unsigned int akc6955_get_freq(void)
 328 {
 329     __bitops_t f, b;
 330     unsigned int i;
 331     unsigned int freq;
 332     unsigned char band;
 333
 334     f.byte = akc6955_readcmd(AKC6955_POWER);
 335     i = akc6955_get_channel();
 336     if(f.b6){ // 25KHz
 337         freq = (i * 5) / 2 + 3000; // freq' = 25*i[KHz] = (25 / 10) *i [10KHz]
 338     } else { // 5K
 339        b.byte = akc6955_readcmd(AKC6955_CH_HI);
 340        akc6955_get_amband(band);
 341        freq = i * 5;
 342        if((band == AKC6955_BAND_MW2) || (b.b5)){
 343            freq = i * 3;
 344        }
 345     }
 346     return freq;
 347 }
 348
 349 void akc6955_set_freq(unsigned int freq)
 350 {
 351     unsigned int ch;
 352     __bitops_t f;
 353     __bitops_t mode3k;
 354     unsigned char band;
 355     unsigned int start, stop;
 356
 357     f.byte = akc6955_readcmd(AKC6955_POWER);
 358     if(f.b6) { // FM
 359         akc6955_get_fmband(band);
 360 //        band &= 7;
 361         if(band == AKC6955_BAND_FMUSER){
 362             start = fm_usrbands[fm_userbandnum].start * 32;
 363             stop = fm_usrbands[fm_userbandnum].stop * 32;
 364         } else {
 365             start = fmbands[band].start;
 366             stop = fmbands[band].end;
 367         }
 368         ch = freq - 3000;
 369         ch = (ch << 2) / 10;
 370     } else {
 371         akc6955_get_amband(band);
 372 //        if(band >= AKC6955_BAND_AMEND) band = AKC6955_BAND_AMEND - 1;
 373         if(band == AKC6955_BAND_AMUSER){
 374             start = am_usrbands[am_userbandnum].start * 32;
 375             stop = am_usrbands[am_userbandnum].stop * 32;
 376         } else {
 377             start = ambands[band].start;
 378             stop = ambands[band].end;
 379         }
 380         mode3k.byte = akc6955_readcmd(AKC6955_CNR_AM);
 381         if(band == AKC6955_BAND_MW2) {
 382             ch = (freq / 9) * 3; // See datasheet.
 383         } else if(band == AKC6955_BAND_MW3) {
 384             ch = freq / 5;
 385         } else  if(mode3k.b7){
 386             ch = freq / 3;
 387         } else {
 388             ch = freq / 5;
 389         }
 390     }
 391     if(freq <  start) freq = start;
 392     if(freq >= stop)   freq = stop - 1;
 393     akc6955_set_tune(mode3k.b7, ch);
 394 }
 395
 396 void akc6955_set_userband(unsigned char start, unsigned char stop, unsigned int ch, unsigned char mode3k)
 397 {
 398     __bitops_t f;
 399
 400     f.byte = akc6955_readcmd(AKC6955_POWER);
 401     akc6955_writecmd(AKC6955_UCH_ST, start);
 402     akc6955_writecmd(AKC6955_UCH_EN, stop);
 403     if(f.b6){
 404         akc6955_set_fmband(AKC6955_BAND_FMUSER);
 405     } else {
 406         akc6955_set_amband(AKC6955_BAND_AMUSER);
 407     }
 408     akc6955_set_tune(mode3k, ch);
 409 }
 410
 411
 412 unsigned char akc6955_get_cnr(void)
 413 {
 414     __bitops_t f;
 415     __bitops_t b;
 416     f.byte = akc6955_readcmd(AKC6955_POWER);
 417     if(f.b6) { // FM
 418         b.byte = akc6955_readcmd(AKC6955_CNR_FM);
 419     } else { // AM
 420         b.byte = akc6955_readcmd(AKC6955_CNR_AM);
 421     }
 422     b.b7 = 0;
 423     return b.byte;
 424 }
 425
 426 int akc6955_read_level(void)
 427 {
 428     __bitops_t f;
 429     unsigned char rflevel, iflevel;
 430     unsigned char b;
 431     int rssi;
 432     unsigned int freq;
 433     int totallevel;
 434     int level;
 435
 436     f.byte = akc6955_readcmd(AKC6955_POWER);
 437     b =  akc6955_readcmd(AKC6955_PGALEVEL);
 438     rflevel = (b & 0xe0) >> 5;
 439     iflevel = (b & 0x1c) >> 2;
 440     totallevel = rflevel + iflevel;
 441
 442     rssi = (int)(akc6955_readcmd(AKC6955_RSSI) & 0x7f);
 443     // totallevel = rssi + 6*totallevel;
 444     level = (int)(totallevel * 6 + rssi);
 445     if(f.b6){
 446         level = 103 - level; // totallevel * 6
 447     } else {
 448         freq = akc6955_get_freq();
 449         if(freq > 2560) { // ASSUME SW
 450             level = 103 - level;
 451         } else { // ASSUME MW,LW
 452             level = 123 - level;
 453         }
 454     }
 455     return level;
 456 }
 457
 458
 459 // Get diff. unit = 100Hz.
 460 int akc6955_get_diff(void)
 461 {
 462     __bitops_t diff;
 463     __bitops_t f;
 464     int n;
 465
 466     diff.byte = akc6955_readcmd(AKC6955_FDNUM);
 467     if(diff.b7) {
 468         diff.b7 = 0;
 469         n = -((int) diff.byte);
 470     } else {
 471         diff.b7 = 0;
 472         n = (int)diff.byte;
 473     }
 474
 475     f.byte = akc6955_readcmd(AKC6955_POWER);
 476     if(f.b6) { // FM
 477         return n * 10;
 478     }
 479     return n; // 10n
 480 }
 481
 482 void akc6955_up_freq(unsigned int step)
 483 {
 484     unsigned int freq;
 485     __bitops_t mode3k;
 486
 487     freq = akc6955_get_channel();
 488     freq += step;
 489     mode3k.byte = akc6955_readcmd(AKC6955_CNR_AM);
 490     akc6955_set_tune(mode3k.b7, freq);
 491 }
 492
 493
 494 void akc6955_down_freq(unsigned int step)
 495 {
 496     unsigned int freq;
 497     __bitops_t mode3k;
 498
 499     freq = akc6955_get_channel();
 500     if(freq <= step) return;
 501     freq -= step;
 502     mode3k.byte = akc6955_readcmd(AKC6955_CNR_AM);
 503     akc6955_set_tune(mode3k.b7, freq);
 504 }
 505
 506 void akc6955_setvolumemode(unsigned char flag)
 507 {
 508     __bitops_t c;
 509     c.byte = akc6955_readcmd(AKC6955_ENABLE);
 510     c.b3 = 0;
 511     if(flag != 0x00){
 512         c.b3 = 1;
 513     }
 514     akc6955_writecmd(AKC6955_ENABLE, c.byte);
 515 }
 516
 517 unsigned char akc6955_getvolumemode(void)
 518 {
 519     __bitops_t c;
 520     c.byte = akc6955_readcmd(AKC6955_ENABLE);
 521     if(c.b3){
 522         return 0xff;
 523     }
 524     return 0;
 525 }
 526
 527 void akc6955_setvolume(unsigned char level)
 528 {
 529 //    unsigned char c;
 530 //    c = akc6955_readcmd(AKC6955_VOLUME) & 0x03;
 531     if(level > 63) level = 63;
 532     akc6955_writecmd(AKC6955_VOLUME, ((akc6955_readcmd(AKC6955_VOLUME) & 0x03) | (level << 2)));
 533 }
 534
 535 unsigned char akc6955_getvolume(void)
 536 {
 537     unsigned char c;
 538     c = akc6955_readcmd(AKC6955_VOLUME) >> 2;
 539     return c;
 540 }
 541
 542 void akc6955_set_prevolume(unsigned char level)
 543 {
 544     unsigned char c;
 545     c = akc6955_readcmd(AKC6955_PRE) & 0xf3;
 546     c |= ((level & 0x03) << 2);
 547     akc6955_writecmd(AKC6955_PRE, c);
 548 }
 549
 550 unsigned char akc6955_get_prevolume(void)
 551 {
 552     unsigned char c;
 553     c = akc6955_readcmd(AKC6955_PRE) & 0x0c;
 554     c >>= 2;
 555     return c;
 556 }
 557
 558
 559 void akc6955_setphase(unsigned char flag)
 560 {
 561     __bitops_t c;
 562     c.byte = akc6955_readcmd(AKC6955_VOLUME);
 563
 564     c.b0 = 1;
 565     if(flag == 0) {
 566         c.b0 = 0; //
 567     }
 568     akc6955_writecmd(AKC6955_VOLUME, c.byte);
 569 }
 570
 571 void akc6955_setline(unsigned char flag)
 572 {
 573     __bitops_t c;
 574     c.byte = akc6955_readcmd(AKC6955_VOLUME);
 575     c.b1 = 1;
 576     if(flag == 0) {
 577         c.b1 = 0;
 578     }
 579     akc6955_writecmd(AKC6955_VOLUME, c.byte);
 580 }
 581
 582 void akc6955_set_lowboost(unsigned char flag)
 583 {
 584     __bitops_t c;
 585     c.byte = akc6955_readcmd(AKC6955_STEREO);
 586     c.b3 = 1;
 587     if(flag == 0) {
 588         c.b3 = 0;
 589     }
 590     akc6955_writecmd(AKC6955_STEREO, c.byte);
 591 }
 592
 593 void akc6955_set_stereomode(unsigned char mode)
 594 {
 595     unsigned char c;
 596     c = akc6955_readcmd(AKC6955_STEREO);
 597     mode = (mode & 0x03) << 2;
 598     c = (c & 0xf3) | mode;
 599     akc6955_writecmd(AKC6955_STEREO, c);
 600 }
 601
 602 unsigned char akc6955_get_stereo(void)
 603 {
 604     unsigned char c;
 605     c = akc6955_readcmd(AKC6955_RCH_HI) & 0x80;
 606     return c;
 607 }
 608
 609 /*
 610  * Get battery level.
 611  * Unit = 0.01V
 612  */
 613
 614 unsigned int akc6955_get_battery(void)
 615 {
 616     unsigned int batt;
 617     unsigned char c;
 618     c = akc6955_readcmd(AKC6955_VBAT) & 0x3f;
 619     batt = 180 + c * 5;
 620     return batt;
 621 }
 622
 623 void akc6955_set_thresh_fmstereo(unsigned char a)
 624 {
 625     unsigned char b;
 626     a = a & 0x03;
 627     threshold_fmstereo = a;
 628     b = akc6955_readcmd(AKC6955_THRESH) & 0xfc;
 629     akc6955_writecmd(AKC6955_THRESH, a | b);
 630 }
 631
 632 void akc6955_set_thresh_width(unsigned char a)
 633 {
 634     unsigned char b;
 635     a = a & 0x03;
 636     threshold_width = a;
 637     a = a << 2; // << 2
 638     b = akc6955_readcmd(AKC6955_THRESH) & 0xf3;;
 639     akc6955_writecmd(AKC6955_THRESH, a | b);
 640 }
 641
 642 void akc6955_set_thresh_amcnr(unsigned char a)
 643 {
 644     unsigned char b;
 645     a = a & 0x03;
 646     threshold_amcnr = a;
 647     a = a << 4; // << 4
 648     b = akc6955_readcmd(AKC6955_THRESH) & 0xcf;
 649     akc6955_writecmd(AKC6955_THRESH, a | b);
 650 }
 651
 652 void akc6955_set_thresh_fmcnr(unsigned char a)
 653 {
 654     unsigned char b;
 655     a = a & 0x03;
 656     threshold_fmcnr = a;
 657     a = a << 6; // << 4
 658     b = akc6955_readcmd(AKC6955_THRESH) & 0x3f;
 659     akc6955_writecmd(AKC6955_THRESH, a | b);
 660 }