mirror of
https://github.com/tjboldt/Apple2-IO-RPi.git
synced 2024-11-24 15:31:14 +00:00
79 lines
2.5 KiB
C
79 lines
2.5 KiB
C
/*
|
|
|
|
MIT License
|
|
|
|
Copyright (c) 2022 Oliver Schmidt (https://a2retro.de/)
|
|
|
|
Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
of this software and associated documentation files (the "Software"), to deal
|
|
in the Software without restriction, including without limitation the rights
|
|
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
copies of the Software, and to permit persons to whom the Software is
|
|
furnished to do so, subject to the following conditions:
|
|
|
|
The above copyright notice and this permission notice shall be included in all
|
|
copies or substantial portions of the Software.
|
|
|
|
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
|
SOFTWARE.
|
|
|
|
*/
|
|
|
|
#include <pico/multicore.h>
|
|
|
|
#include <a2pico.h>
|
|
|
|
#include "board.h"
|
|
|
|
extern const __attribute__((aligned(4))) uint8_t firmware[];
|
|
|
|
static uint32_t page;
|
|
|
|
void __time_critical_func(board)(void) {
|
|
|
|
a2pico_init(pio0);
|
|
|
|
while (true) {
|
|
uint32_t pico = a2pico_getaddr(pio0);
|
|
uint32_t addr = pico & 0x0FFF;
|
|
uint32_t io = pico & 0x0F00; // IOSTRB or IOSEL
|
|
uint32_t strb = pico & 0x0800; // IOSTRB
|
|
uint32_t read = pico & 0x1000; // R/W
|
|
|
|
if (read) {
|
|
if (!io) { // DEVSEL
|
|
switch (addr & 0xF) {
|
|
case 0xB:
|
|
a2pico_putdata(pio0, !multicore_fifo_rvalid() << 7 |
|
|
!multicore_fifo_wready() << 6);
|
|
break;
|
|
case 0xE:
|
|
a2pico_putdata(pio0, sio_hw->fifo_rd);
|
|
break;
|
|
}
|
|
} else {
|
|
if (!strb) {
|
|
a2pico_putdata(pio0, firmware[page | addr]);
|
|
}
|
|
}
|
|
} else {
|
|
uint32_t data = a2pico_getdata(pio0);
|
|
if (!io) { // DEVSEL
|
|
switch (addr & 0xF) {
|
|
case 0x7:
|
|
page = (data & 0x30) << 7;
|
|
break;
|
|
case 0xD:
|
|
sio_hw->fifo_wr = data;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|