Fri, 12 Apr 2013 16:26:25 +0100
Don't set PS1 if there is a level-7 interrupt or bus error
PS1 should only be set if the page was originally present (PS1 or PS0 set). If
PS0 and PS1 are clear (page not present) then do NOT set PS1.
Once again the TRM is blatantly and spectacularly wrong...
1 #ifndef _KEYBOARD_H
2 #define _KEYBOARD_H
4 #include "SDL.h"
6 /// Keyboard buffer size in bytes
7 #define KEYBOARD_BUFFER_SIZE 256
9 typedef struct {
10 /// Key states
11 int keystate[0x80];
13 /// Keyboard buffer
14 uint8_t buffer[KEYBOARD_BUFFER_SIZE];
16 /// Read pointer
17 size_t readp;
19 /// Write pointer
20 size_t writep;
22 /// Number of bytes in keyboard buffer
23 size_t buflen;
25 /// Transmit Interrupt Enable
26 bool txie;
28 /// Receive Interrupt Enable
29 bool rxie;
31 /// "Keyboard State Changed" flag
32 bool update_flag;
33 } KEYBOARD_STATE;
35 /**
36 * Initialise a keyboard state block.
37 *
38 * Call this once when the keyboard is added to the emulation.
39 */
40 void keyboard_init(KEYBOARD_STATE *ks);
42 /**
43 * SDL_Event delegation routine.
44 *
45 * Call this when an SDL keyup or keydown event is received.
46 */
47 void keyboard_event(KEYBOARD_STATE *ks, SDL_Event *ev);
49 /**
50 * Keyboard scan routine.
51 *
52 * Call this periodically to scan the keyboard. 60 times/sec should be fine.
53 */
54 void keyboard_scan(KEYBOARD_STATE *ks);
56 bool keyboard_get_irq(KEYBOARD_STATE *ks);
57 uint8_t keyboard_read(KEYBOARD_STATE *ks, uint8_t addr);
58 void keyboard_write(KEYBOARD_STATE *ks, uint8_t addr, uint8_t val);
60 #endif