stm32/z180-stamp-stm32.c

   1 /*
   2  */
   3
   4 #include <stdio.h>
   5
   6 #include <libopencmsis/core_cm3.h>
   7 #include <libopencm3/cm3/nvic.h>
   8 #include <libopencm3/cm3/systick.h>
   9 #include <libopencm3/stm32/rtc.h>
  10 #include <libopencm3/stm32/rcc.h>
  11 #include <libopencm3/stm32/gpio.h>
  12 #include <libopencm3/stm32/timer.h>
  13
  14 #define ODR     0x0c
  15 #define IDR     0x08
  16
  17
  18 #include "debug.h"
  19 #include "serial.h"
  20 #include "z80-if.h"
  21 #include "../Z180/hdrom.h"
  22
  23
  24 #define ESCCHAR         ('^'-0x40)
  25
  26 #define S_10MS_TO       (1<<0)
  27
  28 /*
  29  * LED Connections
  30  */
  31
  32 #define LED_PORT        GPIOC
  33 #define LED_BLUE_PIN    GPIO8
  34 #define BLUE            8
  35 #define LED_GREEN_PIN   GPIO9
  36 #define GREEN           9
  37
  38
  39 #define LED_BLUE_ON()     BBIO_PERIPH(LED_PORT+ODR, BLUE) = 1
  40 #define LED_BLUE_OFF()    BBIO_PERIPH(LED_PORT+ODR, BLUE) = 0
  41 #define LED_BLUE_TOGGLE() BBIO_PERIPH(LED_PORT+ODR, BLUE) = !BBIO_PERIPH(LED_PORT+ODR, BLUE)
  42
  43 #define LED_GREEN_ON()     BBIO_PERIPH(LED_PORT+ODR, GREEN) = 1
  44 #define LED_GREEN_OFF()    BBIO_PERIPH(LED_PORT+ODR, GREEN) = 0
  45 #define LED_GREEN_TOGGLE() BBIO_PERIPH(LED_PORT+ODR, GREEN) = !BBIO_PERIPH(LED_PORT+ODR, GREEN)
  46
  47
  48 /*
  49  * Button connections
  50  */
  51
  52 //BBIO_PERIPH(GPIOA+IDR, 0);
  53
  54 #define KEY_PORT        GPIOA_IDR
  55 #define KEY0            GPIO0
  56 //#define KEY1          GPIO1
  57 //#define KEY2          GPIO2
  58
  59 #define REPEAT_MASK     KEY0            // repeat: key0
  60 #define REPEAT_START    100             // after 1s
  61 #define REPEAT_NEXT     20              // every 200ms
  62
  63
  64 typedef enum {
  65         NOTHING, PULSE, BLINK1, BLINK2
  66 } LED_MODE;
  67
  68 typedef struct {
  69         uint8_t mode;
  70         uint8_t ontime, offtime;
  71 } led_stat_t;
  72
  73 volatile uint8_t led_timer[2];
  74 led_stat_t led_stat[2];
  75
  76 volatile int timeout_1s;
  77 volatile uint32_t Stat;
  78
  79
  80 /*--------------------------------------------------------------------------*/
  81
  82
  83 static void clock_setup(void)
  84 {
  85         //rcc_clock_setup_in_hse_8mhz_out_24mhz();
  86         rcc_clock_setup_in_hsi_out_24mhz();
  87
  88         /* Enable clocks for:
  89                 GPIO port A (for GPIO_USART1_TX and Button)
  90                 GPIO port C (LEDs)
  91                 USART1
  92                 TIM16 (RST-Pin)
  93                 TIM1  (IOCS1)
  94         */
  95         rcc_peripheral_enable_clock(&RCC_APB2ENR,
  96                           RCC_APB2ENR_IOPAEN | RCC_APB2ENR_IOPBEN
  97                         | RCC_APB2ENR_IOPCEN | RCC_APB2ENR_IOPDEN
  98                         | RCC_APB2ENR_USART1EN | RCC_APB2ENR_AFIOEN
  99                         | RCC_APB2ENR_TIM1EN | RCC_APB2ENR_TIM16EN);
 100         /* Enable clocks for:
 101                 TIM3
 102         */
 103         rcc_peripheral_enable_clock(&RCC_APB1ENR,
 104                         RCC_APB1ENR_TIM3EN);
 105
 106         /* Enable clocks for:
 107                 DMA1
 108         */
 109         rcc_peripheral_enable_clock(&RCC_AHBENR,
 110                         RCC_AHBENR_DMA1EN);
 111 }
 112
 113 static void systick_setup(void)
 114 {
 115         /* SysTick interrupt every N clock pulses: set reload to N-1 */
 116         STK_RVR = 24000000/1000 - 1;
 117
 118         /* Set source to core clock, enable int and start counting. */
 119         STK_CSR = STK_CSR_CLKSOURCE_AHB | STK_CSR_TICKINT | STK_CSR_ENABLE;
 120 }
 121
 122 #if 0
 123 static void nvic_setup(void)
 124 {
 125 //      nvic_enable_irq(NVIC_RTC_IRQ);
 126 //      nvic_set_priority(NVIC_RTC_IRQ, 1);
 127 }
 128 #endif
 129
 130 static void tim3_setup(void)
 131 {
 132         TIM3_CR1 = TIM_CR1_CMS_EDGE | TIM_CR1_DIR_UP;
 133
 134         TIM3_CCMR2 = 0
 135                 | TIM_CCMR2_OC4M_FORCE_LOW
 136         /*      | TIM_CCMR2_OC4M_FORCE_HIGH     */
 137         /*      | TIM_CCMR2_OC4M_PWM2           */
 138
 139         /*      | TIM_CCMR2_OC4PE               */
 140         /*      | TIM_CCMR2_OC4FE               */
 141                 | TIM_CCMR2_CC4S_OUT;
 142
 143         TIM3_CCER = TIM_CCER_CC4E
 144                 | TIM_CCER_CC4P;
 145
 146         TIM3_ARR = 48;  /* default */
 147         TIM3_CCR4 = 1;  /*  */
 148 }
 149
 150 static void gpio_setup(void)
 151 {
 152
 153         /* Disable JTAG-DP, but leave SW-DP Enabled. (free PA15, PB3, PB4)
 154            Remap SPI1 to PB3, PB4, PB5 and PA15.
 155            Remap TIM3 (CH1/PC6, CH2/PC7, CH3/PC8, CH4/PC9)
 156            Port D0/Port D1 mapping on OSC_IN/OSC_OUT
 157         */
 158         gpio_primary_remap(AFIO_MAPR_SWJ_CFG_JTAG_OFF_SW_ON,
 159                         AFIO_MAPR_SPI1_REMAP
 160                         | AFIO_MAPR_TIM3_REMAP_FULL_REMAP
 161                         | AFIO_MAPR_PD01_REMAP);
 162
 163         /* LEDs and User Button. */
 164         gpio_set_mode(LED_PORT, GPIO_MODE_OUTPUT_2_MHZ,
 165                       GPIO_CNF_OUTPUT_PUSHPULL, LED_BLUE_PIN);
 166         gpio_set_mode(LED_PORT, GPIO_MODE_OUTPUT_10_MHZ,
 167                       GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, LED_GREEN_PIN);
 168         gpio_set_mode(GPIOA, GPIO_MODE_INPUT,
 169                       GPIO_CNF_INPUT_FLOAT, GPIO0);
 170 }
 171
 172
 173 /*--------------------------------------------------------------------------*/
 174
 175 void delay_systicks(int ticks)
 176 {
 177         int start, stop, now;
 178
 179         start = STK_CVR;
 180         stop = start - ticks;
 181         if (stop < 0) {
 182                 stop += STK_RVR;
 183                 do {
 184                         now = STK_CVR;
 185                 } while ((now > stop) || (now <= start));
 186         } else {
 187                 do {
 188                         now = STK_CVR;
 189                 } while ((now > stop) && (now <= start));
 190         }
 191 }
 192
 193
 194 /*--------------------------------------------------------------------------*/
 195
 196 static void led_toggle(uint8_t lednr) {
 197         if (lednr == 0)
 198                 LED_BLUE_TOGGLE();
 199         else if (lednr == 1)
 200                 LED_GREEN_TOGGLE();
 201 }
 202
 203 static void led_on(uint8_t lednr) {
 204         if (lednr == 0)
 205                 LED_BLUE_ON();
 206         else if (lednr == 1)
 207                 LED_GREEN_ON();
 208 }
 209
 210 static void led_off(uint8_t lednr) {
 211         if (lednr == 0)
 212                 LED_BLUE_OFF();
 213         else if (lednr == 1)
 214                 LED_GREEN_OFF();
 215 }
 216
 217 static uint8_t led_is_on(uint8_t lednr) {
 218         if (lednr == 0)
 219                 return BBIO_PERIPH(LED_PORT+ODR, BLUE);
 220         else if (lednr == 1)
 221                 return BBIO_PERIPH(LED_PORT+ODR, GREEN);
 222         else
 223                 return 0;
 224 }
 225
 226 static void ledset(uint8_t lednr, uint8_t what, uint8_t len) {
 227
 228         led_stat[lednr].mode = what;
 229         switch (what) {
 230         case PULSE:
 231                 led_stat[lednr].ontime = len;
 232                 led_stat[lednr].offtime = 0;
 233                 led_timer[lednr] = len;
 234                 led_on(lednr);
 235                 break;
 236         case BLINK1:
 237         case BLINK2:
 238                 if (what == BLINK1)
 239                         led_stat[lednr].offtime = 100 - len;
 240                 else
 241                         led_stat[lednr].offtime = 200 - len;
 242                 led_stat[lednr].ontime = len;
 243                 led_timer[lednr] = len;
 244                 led_on(lednr);
 245                 break;
 246         default:
 247                 break;
 248         }
 249 }
 250
 251 /*--------------------------------------------------------------------------*/
 252
 253 static volatile uint16_t key_state,
 254                 key_press, // key press detect
 255                 key_rpt; // key long press and repeat
 256
 257
 258 static uint16_t get_key_press(uint16_t key_mask) {
 259         __disable_irq();
 260         // read and clear atomic !
 261         key_mask &= key_press; // read key(s)
 262         key_press ^= key_mask; // clear key(s)
 263         __enable_irq();
 264         return key_mask;
 265 }
 266
 267 /*
 268 static uint16_t get_key_rpt(uint16_t key_mask) {
 269         __disable_irq();
 270         // read and clear atomic !
 271         key_mask &= key_rpt; // read key(s)
 272         key_rpt ^= key_mask; // clear key(s)
 273         __enable_irq();
 274         return key_mask;
 275 }
 276 */
 277
 278 static uint16_t get_key_short(uint16_t key_mask) {
 279         __disable_irq();
 280         // read key state and key press atomic !
 281         return get_key_press(key_state & key_mask);
 282 }
 283
 284 /*
 285 static uint16_t get_key_long(uint16_t key_mask) {
 286         return get_key_press(get_key_rpt(key_mask));
 287 }
 288 */
 289
 290 static void key_timerproc() {
 291         static uint16_t key_in_last, rpt;
 292         uint16_t key_in, c;
 293
 294         key_in = KEY_PORT;
 295
 296         c = key_in_last & key_in & ~key_state;
 297
 298 //      key_state = key_state  & key_in_last | (key_state  | key_in_last) & key_in;
 299 //      key_state = key_state  & key_in      | (key_state  | key_in)      & key_in_last;
 300
 301         key_state = c | ((key_in_last | key_in) & key_state);
 302
 303 //      key_state = (key_state&key_in_last) | (key_state&key_in) | (key_in_last&key_in);
 304
 305         key_press |= c;
 306
 307         key_in_last = key_in;
 308
 309
 310         if ((key_state & REPEAT_MASK) == 0) // check repeat function
 311                 rpt = REPEAT_START;
 312         if (--rpt == 0) {
 313                 rpt = REPEAT_NEXT; // repeat delay
 314                 key_rpt |= key_state & REPEAT_MASK;
 315         }
 316
 317 }
 318
 319 /*--------------------------------------------------------------------------*/
 320
 321 void sys_tick_handler(void)
 322 {
 323         static int tick_10ms = 0;
 324         static int count_ms = 0;
 325
 326         int i;
 327
 328         ++tick_10ms;
 329         if (tick_10ms == 10)
 330         {
 331                 Stat |= S_10MS_TO;
 332
 333                 tick_10ms = 0;
 334
 335                 i = led_timer[0];
 336                 if (i)
 337                         led_timer[0] = i - 1;
 338                 i = led_timer[1];
 339                 if (i)
 340                         led_timer[1] = i - 1;
 341
 342                 key_timerproc();
 343
 344                 /* Drive timer procedure of low level disk I/O module */
 345                 //disk_timerproc();
 346         }
 347
 348         count_ms++;
 349         if (count_ms == 1000) {
 350                 count_ms = 0;
 351
 352                 i = timeout_1s;
 353                 if (i)
 354                         timeout_1s = i - 1;
 355         }
 356 }
 357
 358 void rtc_isr(void)
 359 {
 360         /* The interrupt flag isn't cleared by hardware, we have to do it. */
 361         rtc_clear_flag(RTC_SEC);
 362
 363 }
 364
 365 /*--------------------------------------------------------------------------*/
 366
 367 void tim3_set(int mode)
 368 {
 369         uint16_t cc_mode;
 370
 371         cc_mode = TIM_CCMR2_CC4S_OUT;
 372
 373         TIM3_CR1 = TIM_CR1_CMS_EDGE | TIM_CR1_DIR_UP /*| TIM_CR1_OPM */ ;
 374
 375         if (mode < 0)
 376                 cc_mode |= TIM_CCMR2_OC4M_FORCE_LOW;
 377         else if (mode == 0)
 378                 cc_mode |= TIM_CCMR2_OC4M_FORCE_HIGH;
 379         else {
 380                 TIM3_ARR = mode;
 381                 TIM3_CCR4 = mode/2;
 382                 cc_mode |= TIM_CCMR2_OC4M_PWM2;
 383         }
 384
 385         TIM3_CCMR2 = cc_mode;
 386
 387         if (mode > 0)
 388                 TIM3_CR1 |= TIM_CR1_CEN;
 389 }
 390
 391 /*--------------------------------------------------------------------------*/
 392
 393 static uint32_t z80_sram_cmp(uint32_t addr, int length, uint8_t wval, int inc)
 394 {
 395         uint8_t rval;
 396         int errors = 0;
 397
 398         DBG_P(1, "SRAM: Check %#.5x byte... ", length);
 399         while (length--) {
 400                 if ((rval = z80_read(addr)) != wval) {
 401                         if (errors == 0) {
 402                                 printf("\nSRAM: Address  W  R\n" \
 403                                        "      -------------\n");
 404 //                                             12345  00 11
 405                         }
 406                         printf("       %.5lx  %.2x %.2x\n", addr, wval, rval);
 407
 408                         if (++errors > 16 )
 409                                 break;
 410                 }
 411                 addr++;
 412                 wval += inc;
 413         }
 414         DBG_P(1, "Done.\n");
 415
 416         return addr;
 417 }
 418
 419 #if 0
 420 static void z80_sram_fill(uint32_t addr, int length, uint8_t startval, int inc)
 421 {
 422         printf("SRAM: Write %#.5x byte... ", length); //fflush(stdout);
 423         while (length--) {
 424                 z80_write(addr, startval);
 425                 ++addr;
 426                 startval += inc;
 427         }
 428         printf("Done.\n");
 429 }
 430
 431
 432 void z80_sram_fill_string(uint32_t addr, int length, const char *text)
 433 {
 434         char c;
 435         const char *p = text;
 436
 437         while (length--) {
 438                 z80_write(addr++, c = *p++);
 439                 if (c == 0)
 440                         p = text;
 441         }
 442 }
 443
 444
 445 uint32_t z80_sram_cmp_string(uint32_t addr, int length, const char *text)
 446 {
 447         char c;
 448         const char *p = text;
 449
 450         while (length--) {
 451                 c = *p++;
 452                 if (z80_read(addr) != c)
 453                         break;
 454                 ++addr;
 455                 if (c == 0)
 456                         p = text;
 457         }
 458         return addr;
 459 }
 460
 461 const char * const qbfox = "Zhe quick brown fox jumps over the lazy dog!";
 462 const char * const qbcat = "Zhe quick brown fox jumps over the lazy cat!";
 463
 464 #endif
 465
 466 uint8_t z80_get_byte(uint32_t adr)
 467 {
 468         uint8_t data;
 469
 470         z80_request_bus();
 471         data = z80_read(adr),
 472         z80_release_bus();
 473
 474         return data;
 475 }
 476
 477
 478 /*--------------------------------------------------------------------------*/
 479
 480 static void do_10ms(void)
 481 {
 482         for (uint_fast8_t i = 0; i < 2; i++) {
 483                 switch (led_stat[i].mode) {
 484                 case PULSE:
 485                         if (led_timer[i] == 0) {
 486                                 led_off(i);
 487                                 led_stat[i].mode = NOTHING;
 488                         }
 489                         break;
 490                 case BLINK1:
 491                 case BLINK2:
 492                         if (led_timer[i] == 0) {
 493                                 if (led_is_on(i))
 494                                         led_timer[i] = led_stat[i].offtime;
 495                                 else
 496                                         led_timer[i] = led_stat[i].ontime;
 497                                 led_toggle(i);
 498                         }
 499                         break;
 500                 default:
 501                         break;
 502                 }
 503         }
 504 }
 505
 506 struct msg_item {
 507         uint8_t fct;
 508         uint8_t sub_min, sub_max;
 509         void (*func)(uint8_t, int, uint8_t *);
 510 };
 511
 512 uint32_t msg_to_addr(uint8_t *msg)
 513 {
 514         uint32_t addr = msg[0] + (msg[1] << 8) + (msg[2] << 16);
 515
 516         return addr;
 517
 518 }
 519
 520 void do_msg_ini_msgfifo(uint8_t subf, int len, uint8_t * msg)
 521 {
 522         (void)subf; (void)len;
 523
 524         z80_init_msg_fifo(msg_to_addr(msg));
 525 }
 526
 527
 528 void do_msg_ini_memfifo(uint8_t subf, int len, uint8_t * msg)
 529 {
 530         (void)len;
 531
 532         z80_memfifo_init(subf - 1, msg_to_addr(msg));
 533 }
 534
 535
 536 void do_msg_char_out(uint8_t subf, int len, uint8_t * msg)
 537 {
 538         (void)subf;
 539
 540         while (len--)
 541                 putchar(*msg++);
 542 }
 543
 544
 545 const struct msg_item z80_messages[] =
 546 {
 547         { 0,
 548           0, 0,
 549           &do_msg_ini_msgfifo},
 550         { 0,
 551           1, 2,
 552           &do_msg_ini_memfifo},
 553         { 1,
 554           1, 1,
 555           &do_msg_char_out},
 556         { 0xff,                         /* end mark */
 557           0, 0,
 558           0},
 559
 560 };
 561
 562
 563
 564
 565 void do_message(int len, uint8_t *msg)
 566 {
 567         uint8_t fct, sub_fct;
 568         int i = 0;
 569
 570         if (len >= 2) {
 571                 fct = *msg++;
 572                 sub_fct = *msg++;
 573                 len -= 2;
 574
 575                 while (fct != z80_messages[i].fct)
 576                         ++i;
 577
 578                 if (z80_messages[i].fct == 0xff) {
 579                         DBG_P(1, "do_message: Unknown function: %i, %i\n",
 580                                         fct, sub_fct);
 581                         return; /* TODO: unknown message # */
 582                 }
 583
 584                 while (fct == z80_messages[i].fct) {
 585                         if (sub_fct >= z80_messages[i].sub_min && sub_fct <= z80_messages[i].sub_max )
 586                                 break;
 587                         ++i;
 588                 }
 589
 590                 if (z80_messages[i].fct != fct) {
 591                         DBG_P(1, "do_message: Unknown sub function: %i, %i\n",
 592                                         fct, sub_fct);
 593                         return; /* TODO: unknown message sub# */
 594                 }
 595
 596                 (z80_messages[i].func)(sub_fct, len, msg);
 597
 598
 599         } else {
 600                 /* TODO: error */
 601                 DBG_P(1, "do_message: to few arguments (%i); this shouldn't happen!\n", len);
 602         }
 603 }
 604
 605
 606
 607 #define CTRBUF_LEN 256
 608
 609 void check_msg_fifo(void)
 610 {
 611         int ch;
 612         static int state;
 613         static int msglen,idx;
 614         static uint8_t buffer[CTRBUF_LEN];
 615
 616         while (state != 3 && (ch = z80_msg_fifo_getc()) >= 0) {
 617                 switch (state) {
 618                 case 0:         /* wait for start of message */
 619                         if (ch == 0x81) {
 620                                 msglen = 0;
 621                                 idx = 0;
 622                                 state = 1;
 623                         }
 624                         break;
 625                 case 1:         /* get msg len */
 626                         if (ch > 0 && ch <= CTRBUF_LEN) {
 627                                 msglen = ch;
 628                                 state = 2;
 629                         } else
 630                                 state = 0;
 631                         break;
 632                 case 2:         /* get message */
 633                         buffer[idx++] = ch;
 634                         if (idx == msglen)
 635                                 state = 3;
 636                         break;
 637                 }
 638         }
 639
 640         if (state == 3) {
 641                 do_message(msglen, buffer);
 642                 state = 0;
 643         }
 644 }
 645
 646
 647 void z80_load_mem(void)
 648 {
 649
 650 DBG_P(1, "Loading z80 memory... \n");
 651
 652         unsigned sec = 0;
 653         uint32_t sec_base = hdrom_start;
 654
 655         while (sec < hdrom_sections) {
 656                 DBG_P(2, "  From: 0x%.5lX to: 0x%.5lX    (%5li bytes)\n",
 657                                 hdrom_address[sec],
 658                                 hdrom_address[sec]+hdrom_length_of_sections[sec] - 1,
 659                                 hdrom_length_of_sections[sec]);
 660
 661                 z80_write_block((unsigned char *) &hdrom[sec_base],  /* src */
 662                                 hdrom_address[sec],                  /* dest */
 663                                 hdrom_length_of_sections[sec]);      /* len */
 664                 sec_base+=hdrom_length_of_sections[sec];
 665                 sec++;
 666         }
 667 }
 668 /*--------------------------------------------------------------------------*/
 669
 670 int main(void)
 671 {
 672         //uint32_t led_state = LED_BLUE_PIN;
 673         //uint32_t rc;
 674         //uint8_t startval = 0;
 675         //int count;
 676         int state = 0;
 677         int ch;
 678
 679         clock_setup();
 680         gpio_setup();
 681         tim3_setup();
 682         setvbuf(stdout, NULL, _IONBF, 0);
 683         serial_setup();
 684         printf("\n(STM32F100+HD64180)_stamp Tester\n");
 685
 686         DBG_P(1, "z80_setup_bus... ");
 687         z80_setup_msg_fifo();
 688         z80_setup_bus();
 689         DBG_P(1, "done.\n");
 690
 691         /*
 692          * If the RTC is pre-configured just allow access, don't reconfigure.
 693          * Otherwise enable it with the LSE as clock source and 0x7fff as
 694          * prescale value.
 695          */
 696         rtc_auto_awake(LSE, 0x7fff);
 697
 698         systick_setup();
 699
 700         DBG_P(1, "Get bus... ");
 701         z80_busreq(LOW);
 702         z80_reset(HIGH);
 703         z80_request_bus();
 704         DBG_P(1, "got it!\n");
 705
 706         z80_memset(0, 0x76, 0x80000);
 707         //z80_sram_fill(0, 512 * 1024, 0x76, 0);
 708         z80_sram_cmp(0, 512 * 1024, 0x76, 0);
 709
 710         z80_load_mem();
 711         z80_reset(LOW);
 712         DBG_P(1, "Bus released!\n");
 713         z80_release_bus();
 714         z80_reset(HIGH);
 715         DBG_P(1, "Reset released!\n");
 716
 717
 718         ledset(0, BLINK1, 50);
 719
 720         while (1) {
 721
 722                 if (Stat & S_10MS_TO) {
 723                         Stat &= ~S_10MS_TO;
 724                         do_10ms();
 725                 }
 726
 727                 if (get_key_short(KEY0)) {
 728                         z80_reset_pulse();
 729                 }
 730
 731                 if ((ch = serial_getc()) >= 0) {
 732                         switch (state) {
 733                         case 0:
 734                                 if (ch == ESCCHAR) {
 735                                         state = 1;
 736                                         /* TODO: Timer starten */
 737                                 } else
 738                                         z80_memfifo_putc(fifo_out, ch);
 739                                 break;
 740                         case 1:
 741                                 switch (ch) {
 742
 743                                 case 'h': /* test: green led on */
 744                                         tim3_set(-1);
 745                                         break;
 746                                 case 'l': /* test: green led off */
 747                                         tim3_set(0);
 748                                         break;
 749                                 case 'p': /* test: pulse on led pin */
 750                                         tim3_set(24000000 / 1000000 * 5); /* 5 us */
 751                                         break;
 752                                 case 'r':
 753                                         z80_reset_pulse();
 754                                         break;
 755
 756                                 case ESCCHAR:
 757                                 default:
 758                                         z80_memfifo_putc(fifo_out, ch);
 759                                 }
 760                                 state = 0;
 761                                 break;
 762                         }
 763                 }
 764
 765                 check_msg_fifo();
 766         }
 767
 768         return 0;
 769 }