code/inventory/bcode.h

@@ -1,43 +1,45 @@
 /*
- * bcode.h - barcode scanner input via the Workabout serial port.
+ * bcode.h - barcode scanner input on the Workabout MX (integral laser).
  *
- * 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".
+ * The Workabout MX integral laser is an UNDECODED (HHLC) scanner: it emits a
+ * raw bar/space signal, not decoded ASCII. The hardware serial decoder in the
+ * RS232/Barcode module only handles wands and wand-emulation scanners (the HC
+ * guide lists "Undecoded Laser Scanner (HHLC)" as unsupported there), which is
+ * why reading TTY:D directly yielded nothing even though the laser's own
+ * good-read LED lit.
+ *
+ * The decode is instead done in software by a barcode decoder LDD. The SDK
+ * ships several (\SIBOSDK\LIB): BAREAN (EAN/UPC), BARC39, BAR128, BARITF,
+ * BARMPLES, BARRAW. Each registers the device "BAR:". For UPC we load BAREAN.
+ *
+ * Usage: bcodeLoad() once, then bcodeOpen() to get a channel, then read it.
+ * The BAREAN.LDD file must be present on the device so p_loadldd can find it.
  */
 #ifndef BCODE_H
 #define BCODE_H
 
 #include <plib.h>
 
+/* Decoder LDD to load (BAREAN.LDD = EAN/UPC) and the device it registers. */
+#define BCODE_LDD "BAREAN"
+#define BCODE_DEV "BAR:"
+
+/* Longest decoded barcode we handle (UPC-A is 12; headroom for EAN/supplements). */
+#define BCODE_MAXLEN 24
+
 /*
- * 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.
+ * Load the UPC/EAN decoder LDD. Returns 0 if loaded, or a negative PLIB error.
+ * E_FILE_EXIST (already loaded) is treated as success by callers.
  */
-#define BCODE_TERM 0x0D
-
-/* Longest decoded barcode we handle (UPC-A is 12; headroom for EAN etc.). */
-#define BCODE_MAXLEN 20
+GLREF_C INT bcodeLoad(VOID);
 
 /*
- * Open the barcode serial channel (TTY:D). Stores the channel handle in
- * *pChan. Returns 0 on success or a negative PLIB error code.
+ * Open a channel to the barcode decoder device (BAR:). Stores it in *pChan.
+ * Returns 0 on success or a negative PLIB error.
  */
 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 */