Programmable Z180 clock, clock command

[z180-stamp.git] / avr / main.c

diff --git a/avr/main.c b/avr/main.c
index 6dbcdefa841a584a74eee75f32716c6d46d26e2a..65622ccfe5316d11d8cb5908809218bb397508c6 100644 (file)
--- a/avr/main.c
+++ b/avr/main.c
@@ -5,32 +5,70 @@
 #include "common.h"
 
 #include <util/delay.h>
-//#include <avr/power.h>
-//#include <avr/pgmspace.h>
 #include <avr/interrupt.h>
-//#include <util/atomic.h>
-//#include <avr/sleep.h>
-//#include <string.h>
-
-#include <util/delay.h>
-
 #include <stdlib.h>
 #include <stdio.h>
 
-
 #include "config.h"
 #include "debug.h"
 #include "z80-if.h"
+#include "i2c.h"
 #include "con-utils.h"
 #include "serial.h"
 #include "timer.h"
 #include "cli.h"
 #include "env.h"
 
+#define udelay(n)  _delay_us(n)
+
+static uint8_t mcusr;
+
 /*--------------------------------------------------------------------------*/
+#if DEBUG
+
+__attribute__ ((naked)) __attribute__ ((section (".init3")))
+void preset_ram (void)
+{
+       for (uint8_t *p = RAMSTART; p <= (uint8_t *) RAMEND; p++)
+               *p = 0xdd;
+
+}
+
+static const FLASH char * const FLASH rreasons[] = {
+                       FSTR("Power on"),
+                       FSTR("External"),
+                       FSTR("Brown out"),
+                       FSTR("Watchdog"),
+                       FSTR("JTAG"),
+               };
+
+static
+void print_reset_reason(void)
+{
+       uint8_t r = mcusr & 0x1f;
+       const FLASH char * const FLASH *p = rreasons;
+
+       printf_P(PSTR("### Reset reason(s): %s"), r ? "" : "none");
+       for ( ; r; p++, r >>= 1) {
+               if (r & 1) {
+                       my_puts_P(*p);
+                       if (r & ~1)
+                               printf_P(PSTR(", "));
+               }
+       }
+       printf_P(PSTR(".\n"));
+}
 
+#endif
+
+static
 void setup_avr(void)
 {
+       /* save and clear reset reason(s) */
+       /* TODO: move to init section? */
+       mcusr = MCUSR;
+       MCUSR = 0;
+
        /* WD */
 
        /* CPU */
@@ -39,9 +77,9 @@ void setup_avr(void)
        MCUCR = _BV(JTD);
        MCUCR = _BV(JTD);
 
-       /* disable unused periphels */
-       PRR0 = _BV(PRTIM2) | _BV(PRTIM0) | _BV(PRADC);
-       PRR1 = _BV(PRTIM5) | _BV(PRTIM4) | _BV(PRTIM3) | 
+       /* disable unused peripherals */
+       PRR0 = _BV(PRTIM0) | _BV(PRADC);
+       PRR1 = _BV(PRTIM5) | _BV(PRTIM4) | _BV(PRTIM3) |
                _BV(PRUSART3) | _BV(PRUSART2) | _BV(PRUSART1);
 
        /* disable analog comparator */
@@ -54,18 +92,19 @@ void setup_avr(void)
 
        /* Timer */
 
-       OCR1A = F_CPU / 8 / 1000 - 1; // Timer1: 1000Hz interval (OC1A)
-       TCCR1B = 0b00001010;
-       TIMSK1 = _BV(OCIE1A); // Enable TC1.oca interrupt
+       OCR2A = F_CPU / 256 / 1000 - 1; /* Timer2: 1000Hz interval (OC2A) */
+       TCCR2A = (0b10 << WGM20);       /* CTC Mode */
+       TCCR2B = (0b110 << CS20);       /* Prescaler 256 */
+       TIMSK2 = _BV(OCIE2A);           /* Enable TC2.oca interrupt */
 }
 
+static
+int reset_reason_is_power_on(void)
+{
+       return (mcusr & _BV(PORF)) != 0;
+}
 
-
-/*******************************************************************************/
-/*******************************************************************************/
-
-#define udelay(n)  _delay_us(n)
-
+/*--------------------------------------------------------------------------*/
 
 /* Stored value of bootdelay, used by autoboot_command() */
 static int  stored_bootdelay;
@@ -73,7 +112,7 @@ static int  stored_bootdelay;
 
 /***************************************************************************
  * Watch for 'delay' seconds for autoboot stop.
- * returns: 0 - no key, allow autoboot 
+ * returns: 0 - no key, allow autoboot
  *          1 - got key, abort
  */
 
@@ -120,23 +159,24 @@ static int abortboot(int  bootdelay)
        return abort;
 }
 
+static
 const char *bootdelay_process(void)
 {
        char *s;
        int bootdelay;
 
-       s = getenv("bootdelay");
-       bootdelay = s ? atoi(s) : CONFIG_BOOTDELAY;
+       bootdelay = (int) getenv_ulong(PSTR("bootdelay"), 10, CONFIG_BOOTDELAY);
 
 
        debug("### main_loop entered: bootdelay=%d\n\n", bootdelay);
        _delay_ms(20);
 
-       s = getenv("bootcmd");
+       s = getenv(PSTR("bootcmd"));
        stored_bootdelay = bootdelay;
        return s;
 }
 
+static
 void autoboot_command(const char *s)
 {
        debug("### main_loop: bootcmd=\"%s\"\n", s ? s : PSTR("<UNDEFINED>"));
@@ -148,6 +188,7 @@ void autoboot_command(const char *s)
 }
 
 
+static
 void main_loop(void)
 {
        const char *s;
@@ -159,17 +200,33 @@ void main_loop(void)
 
 int main(void)
 {
+
        setup_avr();
        z80_setup_bus();
-       
-       serial_setup();
-       sei();
-       
-       if (env_check() == 0)
-               set_default_env();
+
        env_init();
 
+       if (reset_reason_is_power_on())
+               _delay_ms(CONFIG_PWRON_DELAY);
+
+       serial_setup(getenv_ulong(PSTR("baudrate"), 10, CONFIG_BAUDRATE));
+       sei();
+
+#if DEBUG
+       debug("\n=========================<  (RE)START DEBUG  >=========================\n");
+       print_reset_reason();
+#endif
+
+#if DEBUG
+       unsigned long i_speed = getenv_ulong(PSTR("i2c_clock"), 10, CONFIG_SYS_I2C_CLOCK);
+       debug("### Setting I2C clock Frequency to %lu Hz.\n", i_speed);
+       i2c_init(i_speed);
+#else
+       i2c_init(CONFIG_SYS_I2C_CLOCK);
+#endif
+
        printf_P(PSTR("\n(ATMEGA1281+HD64180)_stamp Tester\n"));
-       
+
+
        main_loop();
 }