Cleanups

[uccvend-snackrom.git] / ROM2 / display.c

diff --git a/ROM2/display.c b/ROM2/display.c
index af96921..7da3b10 100644 (file)
--- a/ROM2/display.c
+++ b/ROM2/display.c
@@ -1,6 +1,10 @@
 /*
  * display.c - functions for controlling the display on the vending machine.
  *
+ *
+ * XXX obsolted - with a backend on the server machine, we don't need to
+ * handle scrolling, etc here. Replaced by display_basic.[cho]
+ *
  * Use set_msg(char*) to write a new message to the screen, replacing the
  * previous one. The message can be at most 255 characters long. Use
  * set_wrap_mode with one of the WRAP_* options in vend.h to set the scrolling
@@ -9,32 +13,64 @@
  *
  */
 
+#include "display.h"
 #include "vend.h"
 
 char display_buffer[10];    /* what each byte on the display reads          */
 char current_message[256];  /* message that is scrolled or switched between */
+u8   msg_length;            /* length of current_message                    */
 u8   wrap_mode;             /* whether to scroll or alternate between msgs  */
 u8   scroll_point;          /* how far through the message we have scrolled */
+bool have_scrolled;         /* true after one scroll (used for scroll_msg())*/
 
 /* private prototypes */
 void display_send_byte(char c);
 void display_reset();
 void display_update();
 
-void set_msg(char* newmsg, u8 wrap) {
-       char* dest = current_message;
+void append_msg(char* newmsg, u8 wrap) {
+       char* dest = current_message+msg_length;
        /* equivalent of a string copy */
-       /* while (dest++ = newmsg++); */
        while (newmsg) {
                dest = newmsg;
                dest++;
                newmsg++;
+               msg_length++;
        }
        wrap_mode = wrap;
+}
+
+void set_msg(char* newmsg, u8 wrap) {
+       msg_length = 0;
+       append_msg(newmsg, wrap);
        scroll_point = 0;
        display_update();
 }
 
+void scroll_msg(char* newmsg) {
+       /* puts a message on display and does not return until the message has
+        * scrolled across once.
+        */
+       set_msg(newmsg, WRAP_SCROLL);
+       have_scrolled = 0;
+       while (!have_scrolled);
+}
+
+void display_shift() {
+       /* update the display for WRAP_SCROLL or WRAP_ALTERNATE modes */
+       switch (wrap_mode) {
+               case WRAP_SCROLL:
+               case WRAP_ALTERNATE:
+                       scroll_point++;
+                       if (scroll_point >= msg_length) {
+                               scroll_point = 0;
+                               have_scrolled = 1;
+                       }
+                       display_update();
+                       break;
+       }
+}
+
 void set_char(char c, u8 pos) {
        /* sets a single character */
        display_buffer[pos] = c;
@@ -67,15 +103,18 @@ void display_reset() {
 
 void display_update() {
        u8 i;
+
+       for (i=0; i < 10; i++) {
+               display_buffer[i] = current_message[
+                       (i+(wrap_mode==WRAP_ALTERNATE?scroll_point/10:scroll_point))
+                       %msg_length];
+       }
+
+       /* hmmm, will this cause some flickering of the display? */
        display_reset();
        
        for (i=0; i < 10; i++) {
-               /* FIXME: we may need to fiddle with the character codes sent to the 
-                * controller. It doesn't seem like we have to, but datasheets for
-                * the "pin-for-pin" compatible MSC1937 from OKI suggest a different
-                * character set
-                */
-               display_send_byte(i[display_buffer]&0x7f);
+               display_send_byte(display_buffer[i]&0x7f);
        }
 }