/* * scan.c - Phase 1 barcode diagnostic: decoded laser over the serial port. * * The Workabout MX integral laser powered up and gave a good-read LED on * TTY:D, i.e. it is a DECODED scanner that emits ASCII over the serial port - * no BAR: decoder LDD needed. The earlier TTY:D read returned nothing because * the port's default handshake sets P_OBEY_DSR, and the I/O Devices Reference * states that if the remote device does not assert DSR, an outstanding P_FREAD * is suspended. The laser does not drive DSR, so the read blocked forever. * * This build opens TTY:D, applies a P_SRCHAR config at 9600/8/1 with P_OBEY_DSR * cleared (P_IGN_CTS only, so reads are not gated on modem lines), forces DTR * active, then dumps every byte of each read so the decoded UPC format is seen. * * Blocking I/O; exit via the System screen. */ #include #include GLDEF_C INT main(VOID) { VOID *chan; P_SRCHAR ser; UBYTE buf[64]; UBYTE ctrl[2]; INT err, n, i; err = p_open(&chan, "TTY:D", (UINT)-1); p_printf("open TTY:D: %d\n", err); if (err < 0) { p_printf("Press a key to exit.\n"); p_getch(); return 1; } /* 9600 baud, 8 data bits, 1 stop, no parity; do NOT obey DSR/DCD (only ignore CTS) so a scanner that leaves the modem lines idle can be read. */ ser.tbaud = P_BAUD_9600; ser.rbaud = P_BAUD_9600; ser.frame = P_DATA_8; ser.parity = 0; ser.hand = P_IGN_CTS; ser.xon = 0x11; ser.xoff = 0x13; ser.flags = 0; ser.tmask = 0; err = p_iow(chan, P_FSET, &ser); p_printf("config 9600/8/1: %d\n", err); /* Force DTR (the scanner enable line) active. Opening already drives it, but make it explicit. ctrl[0] is the read-back of input lines. */ ctrl[0] = 0; ctrl[1] = P_SRDTR_ON; err = p_iow(chan, P_FCTRL, ctrl); p_printf("assert DTR: %d\n", err); p_printf("\nScan a barcode. System screen to exit.\n\n"); /* Read ONE byte per call: with tmask=0 a multi-byte P_FREAD waits for the full requested count and would block on a short scan. Streaming single bytes returns each character as it arrives, whatever the terminator. */ for (;;) { n = p_read(chan, buf, 1); if (n < 0) { p_printf("", n); continue; } if (n == 0) continue; i = buf[0]; p_printf(" %d", i); if (i == 13 || i == 10) p_printf(" \n"); } }