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Fix ACIA status/control register, they share the same address (0xa000)

This commit is contained in:
Satoshi N. M 2018-01-13 10:49:44 -08:00
parent f1f1a1f8ac
commit 35ec39e13f
1 changed files with 6 additions and 11 deletions
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17
src/acia6850.c
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@ -13,17 +13,15 @@ extern usbd_device *usbd_dev;
//
#define ACIAControl 0
#define ACIAStatus 1
#define ACIAData 2
#define ACIAStatus 0
#define ACIAData 1
// "MC6850 Data Register (R/W) Data can be read when Status.Bit0=1, and written when Status.Bit1=1."
#define RDRF 1
#define TDRE 2
#define RDRF (1 << 0)
#define TDRE (1 << 1)
uint8_t read6850(uint16_t address) {
switch(address & 3) {
case ACIAControl:
break;
switch(address & 1) {
case ACIAStatus:
return TDRE; // writable
break;
@ -38,13 +36,10 @@ uint8_t read6850(uint16_t address) {
}
void write6850(uint16_t address, uint8_t value) {
switch(address & 3) {
switch(address & 1) {
case ACIAControl:
// TODO: decode baudrate, mode, break control, interrupt
break;
case ACIAStatus:
(void) value;
break;
case ACIAData: {
static char buf[1];
buf[0] = value;