2 * display_basic.c - simple functions for writing to the screen of the vendie.
4 * Use set_msg(char[10]) to write a new message to the screen, replacing the
9 #include "display_basic.h"
12 /* private prototypes */
13 void display_send_byte(char c);
16 void set_msg(char newmsg[10]) {
19 for (i=0; i < 10; i++) {
20 display_send_byte(newmsg[i]&0x7f);
24 void display_send_byte(char c) {
25 bset_misc_output(A3800_DISPLAY_WRITE); /* enable the display clock */
27 _io_ports[M6811_SPDR] = c; /* load SPI with byte */
28 while(!(_io_ports[M6811_SPDR]&M6811_SPIE)); /* wait for completion */
29 _io_ports[M6811_SPDR]; /* SPDR read to clear SPIE flag */
31 bclr_misc_output(A3800_DISPLAY_WRITE); /* disable the display clock */
34 #define DISPLAY_DELAY 100 /* ms to delay between ops - could be tweaked */
35 void display_reset() {
36 /* lower the reset line for a while */
37 bclr((void*)&_io_ports[M6811_PORTA], PORTA_DISP_RESET);
39 bset((void*)&_io_ports[M6811_PORTA], PORTA_DISP_RESET);
44 display_send_byte(0xC0 | 10); /* tell the controller there are 10 digits */
45 display_send_byte(0xE0); /* set duty cycle to 100% */