| 1 | /* (c) 2020 Aaron Taylor <ataylor at subgeniuskitty dot com> */ |
| 2 | /* See LICENSE.txt file for copyright and license details. */ |
| 3 | |
| 4 | #include <stdint.h> |
| 5 | |
| 6 | /* |
| 7 | * Polled console I/O |
| 8 | */ |
| 9 | |
| 10 | #define RCSR (*((volatile uint16_t *)0177560)) |
| 11 | #define RBUF (*((volatile uint16_t *)0177562)) |
| 12 | #define XCSR (*((volatile uint16_t *)0177564)) |
| 13 | #define XBUF (*((volatile uint16_t *)0177566)) |
| 14 | |
| 15 | void |
| 16 | putch(uint16_t c) |
| 17 | { |
| 18 | while((XCSR && 0200) == 0) continue; |
| 19 | XBUF = c; |
| 20 | } |
| 21 | |
| 22 | uint16_t |
| 23 | getch(void) |
| 24 | { |
| 25 | while((RCSR && 0200) == 0) continue; |
| 26 | return RBUF; |
| 27 | } |
| 28 | |
| 29 | /* |
| 30 | * Busy-loop |
| 31 | */ |
| 32 | |
| 33 | void |
| 34 | wait(uint16_t count) |
| 35 | { |
| 36 | while (count--) continue; |
| 37 | } |