Fix rn42.h API

[tmk_firmware.git] / protocol / serial_soft.c

diff --git a/protocol/serial_soft.c b/protocol/serial_soft.c
index b7d06b644e5f60a4fa82fee46f5a78c7af7cd7d2..e8870bcd795f33efe89a6f7c26770de1882fd710 100644 (file)
--- a/protocol/serial_soft.c
+++ b/protocol/serial_soft.c
@@ -43,22 +43,56 @@ POSSIBILITY OF SUCH DAMAGE.
 
 /*
  *  Stupid Inefficient Busy-wait Software Serial
- *  is still useful for negative logic signal like Sun protocol not supported by hardware USART.
+ *  which is still useful for negative logic signal like Sun protocol
+ *  if it is not supported by hardware UART.
+ *
+ *  TODO: delay is not accurate enough. Instruction cycle should be counted and inline assemby is needed.
  */
 
-#define WAIT_US     (1000000/SERIAL_BAUD)
+#define WAIT_US     (1000000L/SERIAL_SOFT_BAUD)
+
+#ifdef SERIAL_SOFT_LOGIC_NEGATIVE
+    #define SERIAL_SOFT_RXD_IN()        !(SERIAL_SOFT_RXD_READ())
+    #define SERIAL_SOFT_TXD_ON()        SERIAL_SOFT_TXD_LO()
+    #define SERIAL_SOFT_TXD_OFF()       SERIAL_SOFT_TXD_HI()
+#else
+    #define SERIAL_SOFT_RXD_IN()        !!(SERIAL_SOFT_RXD_READ())
+    #define SERIAL_SOFT_TXD_ON()        SERIAL_SOFT_TXD_HI()
+    #define SERIAL_SOFT_TXD_OFF()       SERIAL_SOFT_TXD_LO()
+#endif
+
+#ifdef SERIAL_SOFT_PARITY_EVEN
+    #define SERIAL_SOFT_PARITY_VAL      0
+#elif defined(SERIAL_SOFT_PARITY_ODD)
+    #define SERIAL_SOFT_PARITY_VAL      1
+#endif
+
+/* debug for signal timing, see debug pin with oscilloscope */
+#define SERIAL_SOFT_DEBUG
+#ifdef SERIAL_SOFT_DEBUG
+    #define SERIAL_SOFT_DEBUG_INIT()    (DDRD |= 1<<7)
+    #define SERIAL_SOFT_DEBUG_TGL()     (PORTD ^= 1<<7)
+#else
+    #define SERIAL_SOFT_DEBUG_INIT()
+    #define SERIAL_SOFT_DEBUG_TGL()
+#endif
+
 
 void serial_init(void)
 {
-    SERIAL_RXD_INIT();
+    SERIAL_SOFT_DEBUG_INIT();
+
+    SERIAL_SOFT_RXD_INIT();
+    SERIAL_SOFT_TXD_INIT();
 }
 
-// RX ring buffer
+/* RX ring buffer */
 #define RBUF_SIZE   8
 static uint8_t rbuf[RBUF_SIZE];
 static uint8_t rbuf_head = 0;
 static uint8_t rbuf_tail = 0;
 
+
 uint8_t serial_recv(void)
 {
     uint8_t data = 0;
@@ -71,44 +105,120 @@ uint8_t serial_recv(void)
     return data;
 }
 
-//ISR(INT2_vect)
-ISR(SERIAL_RXD_VECT)
+int16_t serial_recv2(void)
+{
+    uint8_t data = 0;
+    if (rbuf_head == rbuf_tail) {
+        return -1;
+    }
+
+    data = rbuf[rbuf_tail];
+    rbuf_tail = (rbuf_tail + 1) % RBUF_SIZE;
+    return data;
+}
+
+void serial_send(uint8_t data)
+{
+    /* signal state: IDLE: ON, START: OFF, STOP: ON, DATA0: OFF, DATA1: ON */
+
+#ifdef SERIAL_SOFT_BIT_ORDER_MSB
+    uint8_t mask = 0x80;
+#else
+    uint8_t mask = 0x01;
+#endif
+
+    uint8_t parity = 0;
+
+    /* start bit */
+    SERIAL_SOFT_TXD_OFF();
+    _delay_us(WAIT_US);
+
+    while (mask) {
+        if (data&mask) {
+            SERIAL_SOFT_TXD_ON();
+            parity ^= 1;
+        } else {
+            SERIAL_SOFT_TXD_OFF();
+        }
+        _delay_us(WAIT_US);
+
+#ifdef SERIAL_SOFT_BIT_ORDER_MSB
+        mask >>= 1;
+#else
+        mask <<= 1;
+#endif
+    }
+
+#if defined(SERIAL_SOFT_PARITY_EVEN) || defined(SERIAL_SOFT_PARITY_ODD)
+    /* to center of parity bit */
+    if (parity != SERIAL_SOFT_PARITY_VAL) {
+        SERIAL_SOFT_TXD_ON();
+    } else {
+        SERIAL_SOFT_TXD_OFF();
+    }
+    _delay_us(WAIT_US);
+#endif
+
+    /* stop bit */
+    SERIAL_SOFT_TXD_ON();
+    _delay_us(WAIT_US);
+}
+
+/* detect edge of start bit */
+ISR(SERIAL_SOFT_RXD_VECT)
 {
-    SERIAL_RXD_INT_ENTER()
+    SERIAL_SOFT_DEBUG_TGL();
+    SERIAL_SOFT_RXD_INT_ENTER()
 
     uint8_t data = 0;
-#ifdef SERIAL_BIT_ORDER_MSB
-    uint8_t pos = 0x80;
+
+#ifdef SERIAL_SOFT_BIT_ORDER_MSB
+    uint8_t mask = 0x80;
 #else
-    uint8_t pos = 0x01;
+    uint8_t mask = 0x01;
 #endif
-    // to center of start bit
+
+    uint8_t parity = 0;
+
+    /* to center of start bit */
     _delay_us(WAIT_US/2);
+    SERIAL_SOFT_DEBUG_TGL();
     do {
-        // to center of next bit
+        /* to center of next bit */
         _delay_us(WAIT_US);
 
-        if (SERIAL_RXD_PIN&(1<<SERIAL_RXD_BIT)) {
-            data |= pos;
+    SERIAL_SOFT_DEBUG_TGL();
+        if (SERIAL_SOFT_RXD_IN()) {
+            data |= mask;
+            parity ^= 1;
         }
-#ifdef SERIAL_BIT_ORDER_MSB
-        pos >>= 1;
+#ifdef SERIAL_SOFT_BIT_ORDER_MSB
+        mask >>= 1;
 #else
-        pos <<= 1;
+        mask <<= 1;
 #endif
-    } while (pos);
-    // to center of stop bit
-    _delay_us(WAIT_US);
+    } while (mask);
 
-#ifdef SERIAL_NEGATIVE_LOGIC
-    data = ~data;
+#if defined(SERIAL_SOFT_PARITY_EVEN) || defined(SERIAL_SOFT_PARITY_ODD)
+    /* to center of parity bit */
+    _delay_us(WAIT_US);
+    if (SERIAL_SOFT_RXD_IN()) { parity ^= 1; }
+    SERIAL_SOFT_DEBUG_TGL();
 #endif
 
+    /* to center of stop bit */
+    _delay_us(WAIT_US);
+
     uint8_t next = (rbuf_head + 1) % RBUF_SIZE;
+#if defined(SERIAL_SOFT_PARITY_EVEN) || defined(SERIAL_SOFT_PARITY_ODD)
+    if ((parity == SERIAL_SOFT_PARITY_VAL) && next != rbuf_tail) {
+#else
     if (next != rbuf_tail) {
+#endif
         rbuf[rbuf_head] = data;
         rbuf_head = next;
     }
 
-    SERIAL_RXD_INT_EXIT();
+    SERIAL_SOFT_RXD_INT_EXIT();
+    SERIAL_SOFT_DEBUG_TGL();
 }