Verified working packet rx at up to 100us clock period and 32 packets all separated by 2ms, both when all pacekts this addr and also when half other addr. 50us clock period working but drops a lot of packets, gets about 3-9 packets out of grouping of 16. Light valve opacity output and timer init/start commented out due to pin clusterfuck of rev 0

Author: second-string

burner.ino

@@ -13,7 +13,7 @@
 #define GREEN_LED PIN_PA7  // GREEN LED
 #define RED_LED PIN_PA6    // RED LED
 
-#define HEARTBEAT_PERIOD_DEFAULT_MS (1000)
+#define HEARTBEAT_PERIOD_DEFAULT_MS (2000)
 #define HEARTBEAT_PERIOD_ERROR_MS (60)
 
 #define DEBUG_MODE 0
@@ -44,7 +44,7 @@ typedef enum {
 
 // TODO :: non-linear opacity mapping here. Lowest values show no change (0 to 10, 10 to 20), then seems solid for a
 // bit, then highest values indistinguishable w/o light behind valve
-static const uint16_t pwm_counts_by_data_value[16] = {
+static const uint16_t pwm_counts_by_data_index[16] = {
     0,
     10,
     20,
@@ -77,19 +77,21 @@ static uint32_t clock_period_us;
 static uint32_t clock_period_padding_us;
 static uint8_t  data_edges_counted;
 static uint8_t  clock_edges_counted;
+static uint16_t edges = 0;
 
-static uint8_t  rx_start_bits;
-static uint8_t  rx_data_bits;
-static uint8_t  device_addr        = 0x1;  // TODO :: eventually this is set dynamically
-static uint16_t current_data_value = 0x0;
-static bool     up                 = true;  // TODO :: debug hack delete
+static uint8_t rx_start_bits;
+static uint8_t rx_data_bits;
+static uint8_t device_addr = 0x1;  // TODO :: eventually this is set dynamically
+static uint8_t rx_data[16] = {0x0};
+static uint8_t rx_data_idx = 0;
 
 /* #if DEBUG_MODE */
 static SoftwareSerial debug_serial(UART_RX, UART_TX);
 /* #endif */
 
 void data_pin_isr(void) {
     data_transition_flag = true;
+    edges++;
 }
 
 ISR(TCA0_OVF_vect) {
@@ -102,9 +104,11 @@ ISR(TCA0_OVF_vect) {
  * Set up timer to expected timeout values and enabled interrupt. Does not start timer
  */
 void timeout_timer_init(void) {
-    // With prescaler of 16 @ 20MHz (aka 1.25MHz) this is ~6.5ms. Currently a full packet is 13 bits @ 500us/bit,
-    // or 6.5ms total.
-    TCA0.SINGLE.PER = 8125 - 1;
+    // With prescaler of 16 @ 20MHz (aka 1.25MHz) 2000 tick period is 1.6ms. Should be se so if in worst case there's
+    // one extra transition at the end of the packet,, timeout timer will still expire and reset state before next
+    // packet starts.
+    // TCA0.SINGLE.PER = 8125 - 1;
+    TCA0.SINGLE.PER = 2000 - 1;
     TCA0.SINGLE.CNT = 0;
 
     // Divide 20MHz down to 5MHz
@@ -189,9 +193,17 @@ void pwm_timer_sync(void) {
     TCD0.CTRLE = TCD_SYNCEOC_bm;
 }
 
+void light_valve_set_opacity(uint8_t opacity_index) {
+    TCD0.CMPACLR = 0x000 + pwm_counts_by_data_index[opacity_index];
+    TCD0.CMPBSET = 0xFFF - pwm_counts_by_data_index[opacity_index];
+
+    // Values will never load into TCD buffers until re synced
+    pwm_timer_sync();
+}
+
 void setup() {
     timeout_timer_init();
-    pwm_timer_init();
+    /* pwm_timer_init(); */
 
     // - set up data pin as input and 2 light valve pins + test GPIO as output and low
     // - start pwm for output valve pins at either fully clear or fully opaque (TODO :: run a fancy startup or bink to
@@ -203,24 +215,23 @@ void setup() {
     // - set up light valve pins as output w/ PWM support
     // - set up timer with no period, that will be set from second pair of transitions in
     /////////////////////////
-    uint8_t bit  = digitalPinToBitMask(DATA_PIN);
-    PORTA.DIRSET = bit;
-    bit          = digitalPinToBitMask(PIN_PA4);
-    PORTA.DIRSET = bit;
-    /* PORTA.DIRCLR = bit; */
+
+    uint8_t bit = digitalPinToBitMask(DATA_PIN);
+    /* PORTA.DIRSET = bit; */
+    /* bit          = digitalPinToBitMask(PIN_PA4); */
+    /* PORTA.DIRSET = bit; */
+    PORTA.DIRCLR = bit;
     /* DATA_PIN_INT_CTRL_REG |= 0x1;   // interrupt on both edges - attiny 212 DS sec. 16.5.11 */
-    /* attachInterrupt(DATA_PIN, data_pin_isr, CHANGE); */
+    attachInterrupt(DATA_PIN, data_pin_isr, CHANGE);
 
     bit          = digitalPinToBitMask(RED_LED);
     PORTA.DIRSET = bit;
     bit          = digitalPinToBitMask(GREEN_LED);
     PORTA.DIRSET = bit;
     PORTA.OUTCLR = 0xFF;
 
-    // TODO :: switch back to normal pindirs for PWM functionality
     bit          = digitalPinToBitMask(UART_TX);
     PORTB.DIRSET = bit;
-    PORTB.OUTCLR = 0xFF;
     bit          = digitalPinToBitMask(UART_RX);
     PORTB.DIRCLR = bit;
     /* bit          = digitalPinToBitMask(LIGHT_VALVE_PIN_1); */
@@ -229,27 +240,26 @@ void setup() {
     /* PORTB.DIRSET = bit; */
     /* PORTB.OUTCLR = 0xFF; */
 
+    // Init globals
     current_state        = DECODE_STATE_IDLE;
     data_transition_flag = false;
+    heartbeat_mode       = HEARTBEAT_MODE_DEBUG;
+    heartbeat_period_ms  = HEARTBEAT_PERIOD_DEFAULT_MS;
+    clock_rate_start_us  = 0;
+    clock_period_us      = (uint32_t)100 * 1000;
+    previous_time        = millis();
+    clock_edge_start     = 0;
+    data_edges_counted   = 0;
+    clock_edges_counted  = 0;
+    rx_data_idx          = 0;
+    memset(rx_data, 0, sizeof(rx_data));
 
-    // Default to toggle heartbeat ever half second. Transition to rapid blink indicates error.
-    heartbeat_mode      = HEARTBEAT_MODE_DEBUG;
-    heartbeat_period_ms = HEARTBEAT_PERIOD_ERROR_MS;
-    clock_rate_start_us = 0;
-    clock_period_us     = (uint32_t)500 * 1000;
-    previous_time       = millis();
-    clock_edge_start    = 0;
-    data_edges_counted  = 0;
-    clock_edges_counted = 0;
-
-    /* #if DEBUG_MODE */
     debug_serial.begin(9600);
-    debug_serial.println("Light valve node firmware");
-    /* #endif */
+    debug_serial.println("LVNF");
 
     // Globally enable interupts
     sei();
-    pwm_timer_start();
+    /* pwm_timer_start(); */
 }
 
 void loop() {
@@ -321,8 +331,13 @@ void loop() {
                 break;
             }
             case DECODE_STATE_MEASURING_CLOCK_RATE: {
-                clock_period_us         = now_us - clock_rate_start_us;
-                clock_period_padding_us = clock_period_us / 10;
+                clock_period_us = now_us - clock_rate_start_us;
+                uint8_t bit     = digitalPinToBitMask(RED_LED);
+                PORTA.OUTTGL    = bit;
+
+                // TODO :: tune this. Can be tight as /10 when clock period >= 200us, but below that need to widen
+                // envelop due to rise/fall time slew of signal at uC pin
+                clock_period_padding_us = clock_period_us / 5;
 
                 LOG("clck per us: ");
                 LOGLN(clock_period_us);
@@ -381,9 +396,8 @@ void loop() {
 
                             current_state = DECODE_STATE_READING_DATA;
                         } else {
-                            debug_serial.println("err DSRS strtbts");
-                            debug_serial.print("start bits: 0b");
-                            debug_serial.println(rx_start_bits, BIN);
+                            LOG("err strtbts: 0b");
+                            LOGLN(rx_start_bits, BIN);
                             current_state = DECODE_STATE_ERROR;
                         }
                     }
@@ -416,8 +430,8 @@ void loop() {
                             break;
                         }
                         default:
-                            debug_serial.print("err DSRD");
-                            debug_serial.println(data_edges_counted);
+                            LOG("err DSRD");
+                            LOGLN(data_edges_counted);
                             current_state = DECODE_STATE_ERROR;
                             break;
                     }
@@ -437,11 +451,15 @@ void loop() {
                         timeout_timer_stop();
                         uint8_t rx_addr_bits = (rx_data_bits & 0xF0) >> 4;
                         if (rx_addr_bits == device_addr) {
-                            debug_serial.print("rx data: 0b");
-                            debug_serial.println((rx_data_bits & 0x0F), BIN);
+                            light_valve_set_opacity(rx_data_bits & 0x0F);
+
+                            LOG("rx data: 0b");
+                            LOGLN((rx_data_bits & 0x0F), BIN);
+                            rx_data[rx_data_idx] = rx_data_bits & 0x0F;
+                            rx_data_idx++;
                         } else {
-                            debug_serial.print("rx wrong addr: ");
-                            debug_serial.println(rx_addr_bits, BIN);
+                            LOG("rx wrong addr: ");
+                            LOGLN(rx_addr_bits, BIN);
                         }
 
                         uint8_t bit   = digitalPinToBitMask(RED_LED);
@@ -475,19 +493,22 @@ void loop() {
             /* PORTA.OUTTGL = bit; */
         }
 
-        if (current_data_value == 15) {
-            up = false;
-        } else if (current_data_value == 0) {
-            up = true;
-        }
-
-        current_data_value += up ? 1 : -1;
+        debug_serial.println(rx_data_idx, DEC);
+        /*
+         * Uncomment to print all 16 debug opacity values saved to debug buffer
+         *
+        if (rx_data_idx > 0) {
+            for (int i = 0; i < rx_data_idx; i++) {
+                debug_serial.print(rx_data[i]);
+                debug_serial.print(", ");
+                rx_data[i] = 0x0;
+                delay(50);
+            }
 
-        TCD0.CMPACLR = 0x000 + pwm_counts_by_data_value[current_data_value];
-        TCD0.CMPBSET = 0xFFF - pwm_counts_by_data_value[current_data_value];
-        debug_serial.print("current_data_value: ");
-        debug_serial.println(current_data_value);
-        pwm_timer_sync();
+            rx_data_idx = 0;
+        }
+        */
+        rx_data_idx = 0;
 
         previous_time = now;
     }