diag(inventory): minimal TTY:D read, no reconfig, one byte at a time

code/inventory/scan.c

@@ -1,59 +1,47 @@
 /*
- * scan.c - Phase 1 barcode diagnostic: pin down the BAR: device.
+ * scan.c - Phase 1 barcode diagnostic: minimal TTY:D barcode-driver read.
  *
- * The scan key is keycode 368 (a Window Server key event an app catches to
- * trigger a scan); the working demo draws the decode itself, so it uses a
- * scanner API - and the only barcode software path in this SDK is the bar*.ldd
- * decoder device "BAR:". Our BAR: open has been failing but its exact error
- * kept scrolling away. This build loads BAREAN, opens BAR:A (then BAR:B),
- * reports each result and HOLDS the screen. If a channel opens, it issues
- * p_iow(P_FREAD) - which should arm the laser - and dumps the decode.
+ * TTY:D is the top-slot bar code interface (I/O Devices Reference, HC
+ * Intelligent Bar Code Reader chapter). Opening it powers the interface and
+ * the scanner; by default the scanner is enabled and in auto-read mode, and it
+ * transmits each decoded label as ASCII text terminated by a carriage return.
+ *
+ * Earlier attempts failed for self-inflicted reasons: a P_FSET forced 9600/8/1
+ * (wrong if the scanner uses another rate, which garbles the data) and a
+ * 64-byte read blocked forever with no terminator set. This build does NEITHER:
+ * it opens TTY:D, changes nothing, and reads ONE byte at a time, streaming each
+ * value. Scan during the brief active window after launch (re-trigger with the
+ * scan key if needed).
  */
 #include <plib.h>
-#include "bcode.h"
 
 GLDEF_C INT main(VOID)
 {
     VOID *chan;
-    UBYTE buf[256];
-    INT   ld, ra, rb, r, i, cnt;
+    UBYTE b;
+    INT   err, n, c;
 
-    ld = p_loadldd(BCODE_LDD);
-    ra = p_open(&chan, "BAR:A", (UINT)-1);
-    if (ra < 0)
-        rb = p_open(&chan, "BAR:B", (UINT)-1);
-    else
-        rb = 0;
-
-    p_printf("load %s: %d\n", BCODE_LDD, ld);
-    p_printf("open BAR:A: %d\n", ra);
-    if (ra < 0)
-        p_printf("open BAR:B: %d\n", rb);
-
-    if (ra < 0 && rb < 0) {
-        p_printf("\nNo BAR channel opened. Press a key.\n");
+    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;
     }
 
-    p_printf("\nOpen. A read should arm the laser - scan now.\n\n");
+    p_printf("Scan now. Streaming bytes:\n\n");
+
     for (;;) {
-        r = p_iow(chan, P_FREAD, buf);   /* arms laser, blocks for a decode */
-        if (r < 0) {
-            p_printf("read status %d\n", r);
+        n = p_read(chan, &b, 1);   /* one byte; no reconfiguration at all */
+        if (n < 0) {
+            p_printf("<e%d>", n);
             continue;
         }
-        cnt = buf[0];
-        if (cnt <= 0) {
-            p_printf("(empty read)\n");
+        if (n == 0)
             continue;
-        }
-        p_printf("cnt=%d type=%d:", cnt, buf[1]);
-        for (i = 1; i <= cnt && i < 256; i++)
-            p_printf(" %d", buf[i]);
-        p_printf("  \"");
-        for (i = 1; i <= cnt && i < 256; i++)
-            p_putch(buf[i] >= ' ' ? buf[i] : '.');
-        p_printf("\"\n");
+        c = b;
+        p_printf(" %d", c);
+        if (c == 13 || c == 10)
+            p_printf(" <EOL>\n");
     }
 }