Diff: SoftSerialSendOnly/SoftSerialSendOnry_tx.cpp

Revision:

0:82d5445a9461

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SoftSerialSendOnly/SoftSerialSendOnry_tx.cpp	Fri Dec 18 04:47:41 2015 +0000
@@ -0,0 +1,80 @@
+#include "SoftSerialSendOnry.h"
+
+int SoftSerialSendOnry::_putc(int c)
+{
+    while(!writeable());
+    prepare_tx(c);
+    tx_bit = 0;
+    txticker.prime();
+    tx_handler();
+    return 0;
+}
+
+void SoftSerialSendOnry::send_break(void) {
+    while(!writeable());
+    tx_bit = 0;         //Just to make sure it appears as non-writable to other threads/IRQs
+    tx->write(0);
+    wait_us((bit_period * _total_bits * 3) / 2);
+    tx->write(1);
+    tx_bit = -1;
+}
+
+int SoftSerialSendOnry::writeable(void)
+{
+    if (!tx_en)
+        return false;
+    if (tx_bit == -1)
+        return true;
+    return false;
+}
+
+void SoftSerialSendOnry::tx_handler(void)
+{
+    if (tx_bit == _total_bits) {
+        tx_bit = -1;
+        fpointer[TxIrq].call();
+        return;
+    }
+
+    //Flip output
+    int cur_out = tx->read();
+    tx->write(!cur_out);
+
+    //Calculate when to do it again
+    int count = bit_period;
+    tx_bit++;
+    while(((_char >> tx_bit) & 0x01) == !cur_out) {
+        count+=bit_period;
+        tx_bit++;
+    }
+
+    txticker.setNext(count);
+}
+
+void SoftSerialSendOnry::prepare_tx(int c)
+{
+    _char = c << 1;
+
+    bool parity;
+    switch (_parity) {
+        case Forced1:
+            _char |= 1 << (_bits + 1);
+        case Even:
+            parity = false;
+            for (int i = 0; i<_bits; i++) {
+                if (((_char >> i) & 0x01) == 1)
+                    parity = !parity;
+            }
+            _char |= parity << (_bits + 1);
+        case Odd:
+            parity = true;
+            for (int i = 0; i<_bits; i++) {
+                if (((_char >> i) & 0x01) == 1)
+                    parity = !parity;
+            }
+            _char |= parity << (_bits + 1);
+    }
+    
+    _char |= 0xFFFF << (1 + _bits + (bool)_parity);
+    _char &= ~(1<<_total_bits);
+}