code/inventory/bcode.h

@@ -0,0 +1,43 @@
+/*
+ * bcode.h - barcode scanner input via the Workabout serial port.
+ *
+ * On the Workabout the barcode module decodes the label in hardware and
+ * delivers the result as an RS232 stream, so a scan is simply read from the
+ * serial channel using the standard PLIB serial I/O. The scanner here is on
+ * the top internal slot, which is port D -> device "TTY:D".
+ */
+#ifndef BCODE_H
+#define BCODE_H
+
+#include <plib.h>
+
+/*
+ * Terminator the scanner appends after each decoded barcode. Most serial
+ * barcode readers send a carriage return (0x0D). If yours sends LF or a
+ * different suffix, change this to match its configuration.
+ */
+#define BCODE_TERM 0x0D
+
+/* Longest decoded barcode we handle (UPC-A is 12; headroom for EAN etc.). */
+#define BCODE_MAXLEN 20
+
+/*
+ * Open the barcode serial channel (TTY:D). Stores the channel handle in
+ * *pChan. Returns 0 on success or a negative PLIB error code.
+ */
+GLREF_C INT bcodeOpen(VOID **pChan);
+
+/* Close a channel opened by bcodeOpen. Safe to call with NULL. */
+GLREF_C VOID bcodeClose(VOID *chan);
+
+/*
+ * Line assembler. Feeds n freshly-read bytes from raw into the caller's line
+ * buffer (current length *pLen, capacity max). When BCODE_TERM is seen the
+ * completed, NUL-terminated barcode is left in line, *pLen is reset to 0 and
+ * 1 is returned. Otherwise returns 0 (more bytes needed). Control bytes below
+ * space (other than the terminator) are ignored; overflow bytes are dropped
+ * until the next terminator.
+ */
+GLREF_C INT bcodeAssemble(UBYTE *raw, INT n, TEXT *line, INT *pLen, INT max);
+
+#endif /* BCODE_H */