avr/chaos: die(), fix read_adc()

die(): 'W" 0xd1ff   causes infinite uninteruptable sleep.
Fix adc_sum shift.
Properly account for the new adc_sum format.
Do not fault read_adc() when wdt_tick.



git-svn-id: svn+ssh://asterix.ieap.uni-kiel.de/home/subversion/stephan/solo/eda/arm/avr@9052 bc5caf13-1734-44f8-af43-603852e9ee25

chaos/chaos.c

@@ -8,7 +8,6 @@ const char *revision =
 	
 	"$Id$";
 
-#define PIN_SSEL (PIND & (1<<PD3))
 #include "spi_slave.h"
 
 #include "ads8688.h"
@@ -16,7 +15,6 @@ const char *revision =
 unsigned char read_adc(unsigned char c, unsigned char n);
 void adc_read(unsigned char chs, unsigned char n);
 unsigned int read_auxadc();
-unsigned int read_hvadc();
 void dac_ramp(unsigned int target);
 void ads8688_cmd(const unsigned char *c, unsigned char *r);
 void ltc1655_cmd(const unsigned char *c);
@@ -27,6 +25,17 @@ void ads8688_config();
 #include "hvosc.h"
 
 #include <avr/interrupt.h>
+#include <avr/sleep.h>
+
+void die()
+{
+	while (1) {
+		cli();
+		set_sleep_mode(SLEEP_MODE_IDLE);
+		sleep_enable();
+		sleep_cpu();
+	}
+}
 
 static inline unsigned char disable_irq()
 {
@@ -66,7 +75,7 @@ static inline void avrdac_set(unsigned int d)
 #include <avr/wdt.h>
 void wdt_init(unsigned char mode);
 unsigned char wdt_count;
-unsigned char wdt_saved;
+volatile unsigned char wdt_tick;
 
 enum {
 	WDT_MODE_LIVE = 2, // = any command kick
@@ -82,52 +91,54 @@ static inline void wdt_kick()
 }
 
 // ADS8688 gains                  Channels:
-// 0: ±2.5     Vref = ± 10.24V    0: Iprim, 0.5V/A, ± 0.64V
-// 1: ±1.25    Vref = ±  5.12V    1: HV Mon, ±5V
-// 2: ±0.625   Vref = ±  2.56V    2: Vdrv, 0…10V 
-// 3: ±0.3125  Vref = ±  1.28V    3: NTC, 0…5V
-// b: ±0.15625 Vref = ±  0.64V    4: Vprim/11, 0…5V
-// 5: 0…2.5    Vref = 0…10.24V    5: 5V/2, 0…5V
-// 6: 0.1,25   Vref = 0… 5.12V    6: I_bias, ±2.56V
-// 7: 0.625    Vref = 0… 2.56V    7: Idrv, 0…10V 
+// 0: ±2.5     Vref = ± 10.24V    0: b: Iprim, 0.5V/A, ± 0.64V
+// 1: ±1.25    Vref = ±  5.12V    1: 5: Vdrv, 0…10V 
+// 2: ±0.625   Vref = ±  2.56V    2: 1: HV Mon, ±5V
+// 3: ±0.3125  Vref = ±  1.28V    3: 6: NTC, 0…5V
+// b: ±0.15625 Vref = ±  0.64V    4: 6: Vprim/11, 0…5V
+// 5: 0…2.5    Vref = 0…10.24V    5: 6: 5V/2, 0…5V
+// 6: 0.1,25   Vref = 0… 5.12V    6: 2: I_bias, ±2.56V
+// 7: 0.625    Vref = 0… 2.56V    7: 5: Idrv, 0…10V 
 // f: 0.3125   Vref = 0… 1.28V    A: dac
 
 #ifndef ADC_GAIN
-#  define ADC_GAINS 0x5266651bUL
+#  define ADC_GAINS 0x5266615bUL
 #endif
 
 #define MAGIC 0xc05c
-#define VERSION 2
+#define VERSION 4
 
 struct conf {
-	unsigned int magic;
-	unsigned char version;
-	unsigned char flags;
-	unsigned char flags2;
-	unsigned int dac;
-	unsigned int dac_nominal;
-	unsigned int dac_off;
-	unsigned int tick_period;
-	unsigned char wdt_timeout;
-	unsigned char wdt_mode;
-	unsigned char wdt_save_addr;
-	unsigned char avradc;
-	unsigned int  avrdac;
-	unsigned int  adcconf;
-	unsigned long adcgain;
-	unsigned char auxadc_n;
-	unsigned char hvadc_ch;
-	unsigned char hvadc_n;
-	unsigned char safe;
-	unsigned int  hvadc_safe;
-	unsigned char ddrc;
-	unsigned char portc;
-	unsigned char portc_on;
-	unsigned char portc_off;
-	unsigned char hvosc_freq;
-	unsigned char hvosc_dc;
-	unsigned char padding[3];
-} conf;
+	unsigned int magic;           //  0
+	unsigned char version;        //  2
+	unsigned char flags;          //  3
+	unsigned char flags2;         //  4
+	unsigned int dac;             //  5
+	unsigned int dac_nominal;     //  7
+	unsigned int dac_off;         //  9
+	unsigned int tick_period;     // 11
+	unsigned char wdt_timeout;    // 13
+	unsigned char wdt_mode;       // 14
+	unsigned char wdt_toggle;     // 15
+	unsigned char avradc;         // 16
+	unsigned int  avrdac;         // 17
+	unsigned int  adcconf;        // 19
+	unsigned long adcgain;        // 21
+	unsigned char auxadc_n;       // 25
+	unsigned char hvadc_ch;       // 26
+	unsigned char hvadc_n;        // 27
+	unsigned char safe;           // 28
+	unsigned int  hvadc_safe;     // 29
+	unsigned char ddrc;           // 31
+	unsigned char portc;          // 32
+	unsigned char portc_on;       // 33
+	unsigned char portc_off;      // 34
+	unsigned char hvosc_freq;     // 35
+	unsigned char hvosc_dc;       // 36
+	unsigned char inpdis;         // 37
+	unsigned char wdt_load;       // 38
+	unsigned char padding;        // 39
+} conf;                               // 40
 
 enum {
 	FLAG_WDT     =   1,
@@ -141,6 +152,7 @@ enum {
 	FLAG2_PC_HV  =   2,
 	FLAG2_HVOSC  =   4,
 	FLAG2_HVLED  =   8,
+	FLAG2_INPDIS  =  16,
 };
 
 __attribute__((section(".eeprom")))
@@ -148,55 +160,64 @@ const struct conf runconf[] = {
 	[0] = { // Default
 		.magic   = MAGIC,
 		.version = VERSION,
+		.flags   = FLAG_RAMP | FLAG_ADCCONF | FLAG_DACADC,
+		.flags2  = FLAG2_HVOSC | FLAG2_HVLED | FLAG2_INPDIS,
+		.wdt_mode        = 1,
 		.wdt_timeout     = 120,   // 2 min
-		.tick_period     = TICK_NS(10000000L), //  10ms ramp
+		.wdt_toggle      = 8,     // sec
+		.tick_period     = TICK_NS(1000000L), //  1ms ramp
 		.avradc          = 0x7f,  // off
 		.adcconf         = 0x8500,// RST
 		.ddrc            = 2,     // OC1B HVOSC
 		.adcgain         = ADC_GAINS,
 		.auxadc_n        = 4,
-		.hvadc_ch        = 1,
-		.hvadc_n         = 4,
-		.hvadc_safe      = 0x8100,
+		.hvadc_ch        = 2,
+		.hvadc_n         = 2,
+		.hvadc_safe      = 0,
+		.inpdis          = 0x3f,
+		.wdt_load        = 20,
 	},
 	[1] = { // ON
 		.magic   = MAGIC,
 		.version = VERSION,
-		.flags   = FLAG_WDT | FLAG_RAMP | FLAG_ADCCONF | FLAG_DACADC,
-		.flags2  = FLAG2_HVOSC | FLAG2_HVLED,
+		.flags   = FLAG_WDT | FLAG_ADCCONF | FLAG_DACADC,
+		.flags2  = FLAG2_HVOSC | FLAG2_HVLED | FLAG2_INPDIS,
+		.wdt_mode        = 4,
 		.wdt_timeout     = 120,   // 2 min
-		.tick_period     = TICK_NS(10000000L), //  10ms ramp
+		.wdt_toggle      = 8,     // sec
+		.tick_period     = TICK_NS(1000000L), //  1ms ramp
 		.avradc          = 0x7f,  // off
 		.adcconf         = 0x8500,// RST
 		.adcgain         = ADC_GAINS,
 		.auxadc_n        = 4,
-		.hvadc_ch        = 1,
-		.hvadc_n         = 4,
-		.hvadc_safe      = 0x8100,
+		.hvadc_ch        = 2,
+		.hvadc_n         = 2,
+		.hvadc_safe      = 0,
 		.ddrc            = 2,     // OC1B HVOSC
-		.hvosc_freq      = 64,
-		.hvosc_dc        = 19,
-		.dac_nominal     = 100,
+		.hvosc_freq      = 55,
+		.hvosc_dc        = 14,
+		.dac_off         = 1000,
+		.dac_nominal     = 34832, // 700 V
+		.inpdis          = 0x3f,
 	},
 	[2] = { // SAFE
 		.magic   = MAGIC,
 		.version = VERSION,
 		.safe    = 1,
-		.flags   = FLAG_WDT | FLAG_RAMP | FLAG_ADCCONF | FLAG_DACADC,
-		.flags2  = FLAG2_HVOSC | FLAG2_HVLED,
+		.flags   = FLAG_WDT | FLAG_RAMP | FLAG_ADCCONF,
+		.flags2  = FLAG2_HVOSC | FLAG2_HVLED | FLAG2_INPDIS,
 		.wdt_timeout     = 120,   // 2 min
-		.tick_period     = TICK_NS(10000000L), //  10ms ramp
+		.wdt_toggle      = 8,     // sec
+		.tick_period     = TICK_NS(1000000L), //  1ms ramp
 		.avradc          = 0x7f,  // off
 		.adcconf         = 0x8500,// RST
 		.adcgain         = ADC_GAINS,
 		.auxadc_n        = 4,
-		.hvadc_ch        = 1,
-		.hvadc_n         = 4,
-		.hvadc_safe      = 0x8100,
+		.hvadc_ch        = 2,
+		.hvadc_n         = 2,
+		.hvadc_safe      = 683 + 0x8000, // 30V
 		.ddrc            = 2,     // OC1B HVOSC
-		.hvosc_freq      = 0,
-		.hvosc_dc        = 0,
-		.dac_nominal     = 0,
+		.inpdis          = 0x3f,
 	},
 };
 
@@ -213,20 +234,23 @@ void conf_init()
 		ads8688_config();
 	if (conf.flags & FLAG_DACADC)
 		conf.dac = read_auxadc(conf.auxadc_n);
-	if (conf.flags & FLAG_RAMP)
-		dac_ramp(conf.dac_nominal);
 	if (conf.flags & FLAG_ADC)
 		avradc_enable(conf.avradc);
 	if (conf.flags & FLAG_DAC)
 		avrdac_set(conf.avrdac);
 	if (conf.flags2 & FLAG2_HVLED) {
-		conf.ddrc |= LED_MASK;
 		led_init();
 	}
 	if (conf.flags2 & FLAG2_PORTC) {
 		PORTC = conf.portc;
 		DDRC = conf.ddrc;
 	}
+	if (conf.flags2 & FLAG2_INPDIS) {
+		DIDR0 = conf.inpdis << 5;
+		DIDR1 = conf.inpdis >> 3;
+	}
+	if (conf.flags & FLAG_RAMP)
+		dac_ramp(conf.dac_nominal);
 }
 
 #include <avr/eeprom.h>
@@ -253,7 +277,8 @@ int hv_is_safe()
 {
 	return !hvosc_is_on()
 		&& conf.dac <= conf.dac_off
-		&& adc_hv <= conf.hvadc_safe
+		&& (!conf.hvadc_safe
+		    || adc_hv <= conf.hvadc_safe)
 		;
 }
 
@@ -267,6 +292,45 @@ void toggle_hv_led()
 	}
 }
 
+void hv_led_on()
+{
+	if (conf.flags2 & FLAG2_HVLED) {
+		if (hv_is_safe())
+			led_on(LED_GREEN);
+		else
+			led_on(LED_RED);
+	}
+}
+
+char spi_was_busy;
+
+static inline
+void spi_busy_init()
+{
+	PCMSK2 |= 8; // PIND3 PCINT19
+	while (!(PIND & 8));
+	PCIFR = 4;
+}
+
+static inline
+unsigned char spi_busy()
+{
+	// Return true if the SSEL pin became low
+	unsigned char f = PCIFR & 4;
+	PCIFR = 4;
+        spi_was_busy = f && !(PIND & 8);
+	return spi_was_busy;
+}
+
+static inline
+void clear_spi_busy()
+{
+	const unsigned char *busy_msg = (const unsigned char *) "\xff\xff\xff" "EEY";
+	if (spi_was_busy && !(PIND & 8))
+		spi_slave_Tx(busy_msg, 6);
+	spi_was_busy = 0;
+}
+
 __attribute__((noinline))
 void hv_safe()
 {
@@ -278,17 +342,33 @@ void hv_safe()
 	ltc1655_cmd(INT2FRAME(conf.dac_off));
 	conf.dac = conf.dac_off;
 	unsigned int adc_last = 0xffff;
-	while (!read_hvadc()) {
-		if (adc_hv < conf.hvadc_safe || adc_hv >= adc_last)
-			break;
-		adc_last = adc_hv;
+	unsigned int toggle = 0;
+	if (conf.hvadc_safe) {
+		spi_busy_init();
+		while (!read_adc(conf.hvadc_ch, conf.hvadc_n)) {
+			if (spi_busy())
+				break;
+			wdt_reset();
+			if (adc_hv < conf.hvadc_safe || adc_hv >= adc_last)
+				break;
+			adc_last = adc_hv;
+			toggle++;
+			if (!toggle)
+				toggle_hv_led();
+		}
 	}
 	enable_irq(sreg);
-	toggle_hv_led();
+	hv_led_on();
 }
 
+unsigned char wdt_killed_us;
+
 int main()
 {
+	wdt_killed_us = MCUSR;
+	MCUSR = 0;
+	wdt_init(0);
+	
 	// turn of unused IO modules
 	PRR = (1<<PRPSC)|(1<<PRCAN)|(1<<PRTIM1)|(1<<PRLIN)|(1<<PRADC);
 	
@@ -296,20 +376,33 @@ int main()
 	DDRB |= (1<<PB0); // make MISO an output
 	ads8688_init();
 	ltc1655_init();
-	hv_safe();
 	eeprom_load(0);
-	if (conf.magic == MAGIC && conf.version == VERSION)
+	
+	if (conf.wdt_load
+	    && wdt_killed_us & (1<<WDRF)
+	    && conf.magic == MAGIC
+	    && conf.version == VERSION) 
+		eeprom_load(conf.wdt_load);
+	if (conf.magic == MAGIC && conf.version == VERSION) {
 		conf_init();
+		if (conf.safe)
+			hv_safe();
+	}
 	while (1) {
+		sei();
+		clear_spi_busy();
 		unsigned char cmd[3];
 		unsigned char resp[3];
 		unsigned char c;
-		unsigned char sreg;
 		const char *p;
-		spi_slave_Rx(cmd, 3);
+		if (spi_slave_Rx_wdt(cmd, 3)) {
+			const unsigned char *wdt_msg =
+				(const unsigned char *) "\xff\xff\xff" "EEW";
+			spi_slave_Tx(wdt_msg, 6);
+			continue;
+		}
+		cli();
 		resp[0] = cmd[0];
-		toggle_hv_led();
-		sreg = disable_irq();
 		if (conf.wdt_mode == WDT_MODE_LIVE)
 			wdt_kick();
 		switch (cmd[0]) {
@@ -328,15 +421,11 @@ int main()
 			int2frame(conf.dac_nominal, resp+1);
 			conf.dac_nominal = frame2int(cmd+1);
 			break;
-		case 'w':
-			int2frame(conf.dac_off, resp+1);
-			conf.dac_off = frame2int(cmd+1);
-			break;
 		case 'H':
 			int2frame(conf.dac, resp+1);
 			if (conf.wdt_mode >= WDT_MODE_HV)
 				wdt_kick();
-			enable_irq(sreg);
+			sei();
 			spi_slave_Tx(resp, 3);
 			dac_ramp(frame2int(cmd+1));
 			continue;
@@ -348,7 +437,7 @@ int main()
 			int2frame(conf.dac, resp+1);
 			if (conf.wdt_mode >= WDT_MODE_HV)
 				wdt_kick();
-			enable_irq(sreg);
+			sei();
 			spi_slave_Tx(resp, 3);
 			dac_ramp(conf.dac_nominal);
 			continue;
@@ -361,6 +450,7 @@ int main()
 				conf.hvosc_dc = cmd[2];
 			}
 			hvosc_init(conf.hvosc_freq, conf.hvosc_dc);
+			hv_led_on();
 			conf.safe = 0;
 			break;
 		case 'I':
@@ -378,7 +468,7 @@ int main()
 		case 't':
 			resp[1] = adc_status;
 			resp[2] = adc_error;
-			enable_irq(sreg);
+			sei();
 			spi_slave_Tx(resp, 3);
 			if (cmd[1]) {
 				if (upcase(cmd[0])) {
@@ -395,20 +485,17 @@ int main()
 			if (c>8)
 				c = 8;
 			switch (cmd[2]) {
-			case 1: int2frame(adc_sum[c], resp+1); break;
-			case 2: resp[1] = adc_sum[c] >> 16; resp[2] = adc_n[c]; break;
+			case 1: int2frame(adc_sum[c] >> 8, resp+1); break;
+			case 2: resp[1] = adc_sum[c]; resp[2] = adc_n[c]; break;
 			case 3: int2frame(adc_noise[c], resp+1); break;
 			default: resp[1] = adc_status; resp[2] = adc_error; break;
 			}
 			break;
 		case 'r':
-			if (adc_error) {
-				resp[0] = 'E';
-				resp[1] = 'r';
-				resp[2] = adc_error;
-				break;
-			}
-			int2frame(adc_aux, resp+1);
+			if (cmd[1])
+				int2frame(adc_hv, resp+1);
+			else
+				int2frame(adc_aux, resp+1);
 			break;
 		case 'V':
 			p = revision;
@@ -420,18 +507,26 @@ int main()
 			resp[1] = *p;
 			resp[2] = cmd[1]-c;
 			break;
+		case 'w':
+			resp[1] = conf.wdt_mode;
+			resp[2] = wdt_count;
+			sei();
+			spi_slave_Tx(resp, 3);
+			hv_safe();
+			break;
 		case 'W':
+			if (cmd[1]==0xff && cmd[2]==0xd1)
+				die();
 			resp[1] = conf.wdt_mode;
 			resp[2] = conf.wdt_timeout;
 			if (cmd[2])
 				conf.wdt_timeout = cmd[2];
-			if (cmd[1]) {
+			if (cmd[1])
 				wdt_init(cmd[1]);
-				sreg = (1<<SREG_I);
-			}
 			else {
 				resp[2] = wdt_count;
 				wdt_kick();
+				toggle_hv_led();
 			}
 			break;
 		case 'm':
@@ -449,7 +544,7 @@ int main()
 		case 'S':
 			resp[1] = cmd[1];
 			resp[2] = sizeof(conf);
-			enable_irq(sreg);
+			sei();
 			spi_slave_Tx(resp, 3);
 			eeprom_save(cmd[1]);
 			continue;
@@ -465,7 +560,7 @@ int main()
 					break;
 			}
 			if (cmd[1] && upcase(cmd[1])) {
-				enable_irq(sreg);
+				sei();
 				spi_slave_Tx(resp, 3);
 				conf_init();
 				continue;
@@ -533,8 +628,20 @@ int main()
 			if (!upcase(cmd[0]))
 				*(unsigned char *)(cmd[1]+0) = cmd[2];
 			break;
+		case 'Z':
+		case 'z':
+			resp[1] = cmd[1];
+			switch (cmd[1]) {
+			case 0: resp[2] = wdt_killed_us; break;
+			}
+			if (upcase(cmd[0]))
+				break;
+			switch (cmd[1]) {
+			case 0: wdt_killed_us = cmd[2]; break;
+			}
+			break;
 		}
-		enable_irq(sreg);
+		sei();
 		spi_slave_Tx(resp, 3);
 	}
 }
@@ -555,8 +662,13 @@ void ads8688_config()
 			}, r);
 }
 
+volatile unsigned char adc_lock;
+
 unsigned char read_adc(unsigned char c, unsigned char n)
 {
+	unsigned char e = 0;
+	if (n>8)
+		n=8;
 	unsigned char nn = (1<<n) - 1;
 	unsigned char cc;
 	if (c >= 8) {
@@ -566,42 +678,58 @@ unsigned char read_adc(unsigned char c, unsigned char n)
 	else
 		cc = 1<<c;
 		
-	spi_int_init();
 	unsigned char cmd[2] = {0, 0xc0 | (c << 2)};
 	unsigned char resp[2];
 	unsigned char i;
+	adc_lock = 1;
+	unsigned char sreg = disable_irq();
 	for (i=0; i<3; i++)
 		ads8688_cmd(cmd, resp);
+	enable_irq(sreg);
 	unsigned int s0 = frame2int(resp);
 	unsigned long s = s0;
 	int r = 0;
 	unsigned long q = 0;
+	spi_busy_init();
 	for (i=0; i<nn; i++) {
-		if (spi_int())
-			return adc_error |= cc;
-		unsigned char sreg = disable_irq();
+		if (spi_busy()) {
+			e = adc_error |= cc;
+			goto out;
+		}
+		sreg = disable_irq();
 		ads8688_cmd(cmd, resp);
 		enable_irq(sreg);
 		unsigned int s1 = frame2int(resp);
 		s += s1;
-		char d = s1 - s0;
+		int dd = s1 - s0;
+		if (dd > 127)
+			dd = 127;
+		if (dd < -127)
+			dd = -127;
+		signed char d = dd;
 		r += d;
 		q += d * d;
 	}
 	unsigned long rr = (long)r*r;
-	unsigned long qq = (nn+1)*q;
-	unsigned long chi2 = qq-rr;
-	adc_sum[c] = s;
-	adc_noise[c] = chi2 >> n;
+	unsigned long qq = q << n;
+	unsigned long chi2 = qq - rr;
+	adc_sum[c] = s << (8-n);
+	chi2 >>= 2*n - 1;
+	chi2 += 1;
+	chi2 >>= 1;
+	adc_noise[c] = chi2;
 	adc_n[c] = n;
 	adc_status |= cc;
-	return 0;
+	if (c == conf.hvadc_ch)
+		adc_hv  = adc_sum[c] >> 8;
+out:
+	adc_lock = 0;
+	return e;
 }
 
 
 void adc_read(unsigned char chs, unsigned char n)
 {
-	spi_int_init();
 	adc_status = 0;
 	adc_error = 0;
 	unsigned char c;
@@ -610,34 +738,24 @@ void adc_read(unsigned char chs, unsigned char n)
 			continue;
 		if (read_adc(c, n))
 			return;
-		if (c==conf.hvadc_ch)
-			adc_hv = adc_sum[c] >> n;
 	}
 }
 
-unsigned int read_hvadc()
-{
-	unsigned char n = conf.hvadc_n;
-	unsigned char c = conf.hvadc_ch;
-	if (!read_adc(c, n))
-		adc_hv  = adc_sum[c] >> n;
-	return adc_hv;
-}
-
 unsigned int read_auxadc()
 {
 	unsigned char n = conf.auxadc_n;
 	if (!read_adc(8, n))
-		adc_aux  = adc_sum[8] >> n;
+		adc_aux  = adc_sum[8] >> 8;
 	return adc_aux;
 }
 
 void dac_ramp(unsigned int target)
 {
 	conf.safe = 0;
-	spi_int_init();
+	unsigned char toggle = 0;
+	spi_busy_init();
 	while (conf.dac != target) {
-		if (spi_int())
+		if (spi_busy())
 			return;
 		if (!tick(TICKO))
 			continue;
@@ -649,24 +767,36 @@ void dac_ramp(unsigned int target)
 			conf.dac = target;
 		ltc1655_cmd(INT2FRAME(conf.dac));
 		enable_irq(sreg);
+		toggle++;
+		if (!toggle)
+			toggle_hv_led();
 	}
+	hv_led_on();
 }
 
 ISR(WDT_vect)
 {
-	if (conf.safe && !hv_is_safe())
-		read_hvadc();
-	toggle_hv_led();
-	if (wdt_count++ < conf.wdt_timeout)
-		goto wdt_out;
-	hv_safe();
 	wdt_reset();
-	if (conf.wdt_save_addr && !wdt_saved) {
-		wdt_saved = 1;
-		eeprom_save(conf.wdt_save_addr);
+	wdt_count++;
+	if (wdt_count >= conf.wdt_toggle) {
+		if (conf.safe && conf.hvadc_safe && !adc_lock) {
+			adc_hv = 0;
+			read_adc(conf.hvadc_ch, conf.hvadc_n);
+		}
+		toggle_hv_led();
 	}
+	if (wdt_count < conf.wdt_timeout)
+		goto wdt_out;
+	wdt_count = 0;
+	hv_safe();
 wdt_out:
-	WDTCSR |= WDIE;
+	__asm__("STS %[CSR], %[CE]"     "\n\t"
+		"STS %[CSR], %[IE]"     "\n"
+		::[CSR] "n" (&WDTCSR),
+		 [CE] "r" ((unsigned char)(1<<WDCE | 1<<WDE | 1<<WDP2 | 1<<WDP1)),
+		 [IE] "r" ((unsigned char)(1<<WDIE | 1<<WDE | 1<<WDP2 | 1<<WDP1))
+		);
+	wdt_tick = 1;
 }
 
 void wdt_init(unsigned char mode)
@@ -674,7 +804,12 @@ void wdt_init(unsigned char mode)
 	conf.wdt_mode = mode;
 	wdt_reset();
 	if (mode < WDT_MODE_LIVE) {
-		WDTCSR = 0;
+		__asm__("STS %[CSR], %[CE]"     "\n\t"
+			"STS %[CSR], %[IE]"     "\n"
+			::[CSR] "n" (&WDTCSR),
+			 [CE] "r" ((unsigned char)(1<<WDCE | 1<<WDIE | 1<<WDE | 1<<WDP2 | 1<<WDP1)),
+			 [IE] "r" ((unsigned char)(1<<WDP2 | 1<<WDP1))
+			);
 		return;
 	}
 	// 1s timeout, WDT interrupt enabled
@@ -713,10 +848,4 @@ void avradc_enable(unsigned char c)
 	if (!(c&0x80))
 		ADCSRA |= 1<<ADEN;
 	ADCSRA |= 1<<ADSC;
-	if (cc==4)
-		; // SPI SCK
-	else if (cc<8)
-		DIDR0 = 1<<cc;
-	else if (cc<11)
-		DIDR1 = 1<<(cc&3);
 }

chaos/hvosc.h

@@ -2,13 +2,15 @@
 
 static inline void hvosc_init(unsigned char freq, unsigned char dc)
 {
+	PORTC &=~ (1<<PC1);
+	PORTD &=~ (1<<PD2);
+	DDRC |= (1<<PC1);
+	DDRD |= (1<<PD2);
 	if (!dc || freq <= dc) {
 		TCCR1A = 0;
 		return;
 	}
 	PRR &=~ (1<<PRTIM1);
-	DDRC |= (1<<PC1);
-	DDRD |= (1<<PD2);
 	TCCR1A = (2<<COM1A0) | (3<<COM1B0) | (2<<WGM10);
 	TCCR1B = (1<<CS10) | (2<<WGM12);
 	ICR1H = 0;

spi_slave.h

@@ -32,7 +32,28 @@ static inline void spi_slave_Rx(unsigned char d[], unsigned char n)
 	}
 }
 
-static inline void spi_slave_Tx(unsigned char d[], unsigned char n)
+extern volatile unsigned char wdt_tick;
+static inline char spi_slave_Rx_wdt(unsigned char d[], unsigned char n)
+{
+	SPSR;
+	SPDR;
+	register unsigned char b;
+	do {
+		while (!(SPSR & SPSR_IF));
+		wdt_tick = 0;
+		SPDR = 0xff;
+		b = SPDR;
+	} while (b&0x80);
+	*d++ = b;
+	while (--n) {
+		while (!(SPSR & SPSR_IF));
+		SPDR = 0xff;
+		*d++ = SPDR;
+	}
+	return wdt_tick;
+}
+
+static inline void spi_slave_Tx(const unsigned char d[], unsigned char n)
 {
 	SPSR;
 	SPDR;
@@ -55,17 +76,3 @@ static inline unsigned int frame2int(unsigned char *f)
 }
 #define INT2FRAME(i) ((unsigned char []){i, i>>8})
 
-#ifdef PIN_SSEL
-
-static inline unsigned int spi_int()
-{
-	// Return true if the SSEL pin is low
-	return !PIN_SSEL;
-}
-
-static inline void spi_int_init()
-{
-	while (spi_int());
-}
-
-#endif