Initial KISS support

Modem/protocol/KISS.c

@@ -0,0 +1,81 @@
+#include <stdlib.h>
+#include <string.h>
+#include <avr/eeprom.h>
+#define F_CPU 16000000UL
+#include <util/delay.h>
+#include <drv/timer.h>      // Timer driver from BertOS
+#include "KISS.h"
+
+static uint8_t serialBuffer[CONFIG_AX25_FRAME_BUF_LEN+1]; // Buffer for holding incoming serial data
+AX25Ctx *ax25ctx;
+Serial *serial;
+size_t frame_len;
+bool IN_FRAME;
+bool ESCAPE;
+uint8_t command = CMD_UNKNOWN;
+unsigned long kiss_preamble = CONFIG_AFSK_PREAMBLE_LEN;
+unsigned long kiss_tail = CONFIG_AFSK_TRAILER_LEN;
+
+void kiss_init(AX25Ctx *ax25, Serial *ser) {
+    ax25ctx = ax25;
+    serial = ser;
+}
+
+void kiss_messageCallback(AX25Ctx *ctx) {
+    kfile_putc(FEND, &serial->fd);
+    kfile_putc(0x00, &serial->fd);
+    for (unsigned i = 0; i < ctx->frm_len; i++) {
+        uint8_t b = ctx->buf[i];
+        if (b == FEND) {
+            kfile_putc(FESC, &serial->fd);
+            kfile_putc(TFEND, &serial->fd);
+        } else if (b == FESC) {
+            kfile_putc(FESC, &serial->fd);
+            kfile_putc(TFESC, &serial->fd);
+        } else {
+            kfile_putc(b, &serial->fd);
+        }
+    }
+    kfile_putc(FEND, &serial->fd);
+}
+
+void fon(void) {
+    long ts = 300000;
+    while (ts--) PORTB |= BV(2);
+}
+
+
+void kiss_serialCallback(uint8_t sbyte) {
+    if (IN_FRAME && sbyte == FEND && command == CMD_DATA) {
+        IN_FRAME = false;
+        ax25_sendRaw(ax25ctx, serialBuffer, frame_len);
+    } else if (sbyte == FEND) {
+        IN_FRAME = true;
+        command = CMD_UNKNOWN;
+        frame_len = 0;
+    } else if (IN_FRAME && frame_len < CONFIG_AX25_FRAME_BUF_LEN) {
+        // Have a look at the command byte first
+        if (frame_len == 0 && command == CMD_UNKNOWN) {
+            // MicroModem supports only one HDLC port, so we
+            // strip off the port nibble of the command byte
+            sbyte = sbyte & 0x0F;
+            command = sbyte;
+        } else if (command == CMD_DATA) {
+            if (sbyte == FESC) {
+                ESCAPE = true;
+            } else {
+                if (ESCAPE) {
+                    if (sbyte == TFEND) sbyte = FEND;
+                    if (sbyte == TFESC) sbyte = FESC;
+                    ESCAPE = false;
+                }
+                serialBuffer[frame_len++] = sbyte;
+            }
+        } else if (command == CMD_TXDELAY) {
+            kiss_preamble = sbyte * 10UL;
+        } else if (command == CMD_TXTAIL) {
+            kiss_tail = sbyte * 10;
+        } 
+        
+    }
+}

Modem/protocol/KISS.h

@@ -1,10 +1,27 @@
-#ifndef PROTOCOL_KISS
-#define PROTOCOL_KISS 0x02
+#ifndef _PROTOCOL_KISS
+#define _PROTOCOL_KISS 0x02
 
 #define FEND 0xC0
 #define FESC 0xDB
 #define TFEND 0xDC
 #define TFESC 0xDD
 
+#define CMD_UNKNOWN 0xFE
+#define CMD_DATA 0x00
+#define CMD_TXDELAY 0x01
+#define CMD_P 0x02
+#define CMD_SLOTTIME 0x03
+#define CMD_TXTAIL 0x04
+#define CMD_FULLDUPLEX 0x05
+#define CMD_SETHARDWARE 0x06
+#define CMD_RETURN 0xFF
 
+#include <net/ax25.h>
+#include <drv/ser.h>
+
+void kiss_init(AX25Ctx *ax25, Serial *ser);
+
+void kiss_messageCallback(AX25Ctx *ctx);
+void kiss_serialCallback(uint8_t sbyte);
+void fon(void);
 #endif

Modem/protocol/SimpleSerial.h

@@ -1,9 +1,8 @@
-#ifndef PROTOCOL_SIMPLE_SERIAL
+#ifndef _PROTOCOL_SIMPLE_SERIAL
+#define _PROTOCOL_SIMPLE_SERIAL 0x01
 #include <net/ax25.h>
 #include <drv/ser.h>
 
-#define PROTOCOL_SIMPLE_SERIAL 0x01
-
 #define DEFAULT_CALLSIGN "NOCALL"
 #define DEFAULT_DESTINATION_CALL "APZMDM"