Initial commit of UART-LIN slave. Receiving Break does not work.

diff --git a/misc/tty_lin_slave/Makefile b/misc/tty_lin_slave/Makefile
new file mode 100644 (file)
index 0000000..6bf535a
--- /dev/null
+++ b/misc/tty_lin_slave/Makefile
@@ -0,0 +1,2 @@
+all: main.c
+       gcc main.c -std=gnu99 -Wall -pedantic -o main

diff --git a/misc/tty_lin_slave/main.c b/misc/tty_lin_slave/main.c
new file mode 100644 (file)
index 0000000..68a8d4a
--- /dev/null
+++ b/misc/tty_lin_slave/main.c
@@ -0,0 +1,136 @@
+/*
+ * PCAN-LIN, RS-232 to CAN/LIN converter control application
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <termios.h>
+#include <stdint.h>
+
+#define LIN_HDR_SIZE           2
+#define LIN_PKT_MAX_SIZE       16 /* FIXME */
+struct termios term_attr;
+/* ------------------------------------------------------------------------ */
+
+int read_header(int tty)
+{
+       int p0, p1; /* Parity bits */
+       int par_rec; /* Parity received as a part of a packet */
+       int par_calc; /* Calculated parity */
+       int received = 0;
+       uint8_t buff[LIN_HDR_SIZE];
+       memset(buff, '\0', sizeof(buff));
+
+       while (1) {
+               received = read(tty, &buff[0], 1);
+               if (received == -1)
+                       perror("read()");
+               
+               if (buff[0] != 0x55) /* Sync byte field */
+                       continue;
+
+               received = read(tty, &buff[1], 1);
+               if (received == -1)
+                       perror("read()");
+               else
+                       break;
+       }
+
+       p0 = ((buff[1] >> 8) ^ (buff[1] >> 7) ^ (buff[1] >> 6) ^ (buff[1] >> 4)) & 0x1;
+       p1 = ~(((buff[1] >> 8) ^ (buff[1] >> 5) ^ (buff[1] >> 4) ^ (buff[1] >> 3))) & 0x1;
+
+       printf("%02X ", buff[0]);
+       printf("%02X ", buff[1]);
+
+       par_rec = buff[1] & 0x3;
+       par_calc = p1 | (p0 << 1);
+       printf("| LIN id: %02X ", buff[1] & 0xfc);
+       printf("| par_rec: %X; par_calc: %X ", par_rec, par_calc);
+       if (par_rec == par_calc)
+               printf("parity OK");
+       
+       printf("\n");
+
+       return 0;
+}
+
+static void reset_input_mode(int tty)
+{
+       tcsetattr(tty, TCSANOW, &term_attr);
+}
+
+static void set_input_mode(int tty)
+{
+       int status;
+       struct termios tattr;
+
+       /* Flush input and output queues. */
+       if (tcflush(tty, TCIOFLUSH) != 0) {
+               perror("tcflush");
+               exit(EXIT_FAILURE);
+       }
+
+       /* Fetch the current terminal parameters. */
+       if(!isatty(tty)) {
+               fprintf(stderr, "Not a terminal.\n");
+               exit(EXIT_FAILURE);
+       }
+
+       /* Save settings for later restoring */
+       tcgetattr(tty, &term_attr);
+
+       /* RAW mode */
+       tcgetattr(tty, &tattr);
+       tattr.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP
+                               | INLCR | IGNCR | ICRNL | IXON);
+       tattr.c_oflag &= ~OPOST;
+       tattr.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
+       tattr.c_cflag &= ~(CSIZE | PARENB);
+       tattr.c_cflag |= CS8;
+
+       tattr.c_cc[VMIN] = 1;
+       tattr.c_cc[VTIME] = 0;
+
+       /* Set TX, RX speed */
+       cfsetispeed(&tattr, B19200);
+       cfsetospeed(&tattr, B19200);
+
+       status = tcsetattr(tty, TCSANOW, &tattr);
+       if (status == -1)
+               perror("tcsetattr()");
+
+}
+
+int main(int argc, char* argv[])
+{
+       char dev[32];
+       int tty;
+
+       if (argc < 2) {
+               fprintf(stderr, "Device is missing\n");
+               fprintf(stderr, "Usage: %s DEVICE\n", argv[0]);
+               return -3;
+       }
+
+       strncpy((char*)&dev, argv[1], 32);
+       tty = open(dev, O_RDWR);
+       if (tty < 0) {
+               perror("open()");
+               return -4;
+       }
+
+       /* Configure UART */
+       set_input_mode(tty);
+
+       while(1) {
+               read_header(tty);
+       }       
+
+       reset_input_mode(tty);
+       close(tty);
+
+       return EXIT_SUCCESS;
+}