f256/f256lib/f256.c
2024-01-07 17:10:41 -06:00

103 lines
3.1 KiB
C

/*
* Copyright (c) 2024 Scott Duensing, scott@kangaroopunch.com
*
* 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 "f256.h"
#include "text.c"
#include "bitmap.c"
#include "dma.c"
void f256Init(void) {
byte mmu = PEEK(MMU_IO_CTRL); // Get current MMU state.
asm("sei");
POKE(MMU_IO_CTRL, MMU_IO_PAGE_0); // Swap I/O page 0 into bank 6.
//POKE(VKY_MSTR_CTRL_0, 1); // Enable text.
//POKE(VKY_MSTR_CTRL_0, 12); // Enable bitmaps.
POKE(VKY_MSTR_CTRL_0, 15); // Enable text and bitmaps.
//POKE(VKY_MSTR_CTRL_0, 63); // Enable text and all graphics.
//POKE(VKY_MSTR_CTRL_1, 20); // Enable FON_OVLY and DBL_Y.
POKE(VKY_MSTR_CTRL_1, 4); // Enable DBL_Y.
POKE(MMU_IO_CTRL, mmu); // Restore MMU state.
POKE(MMU_MEM_CTRL, 0xb3); // MLUT editing enabled, editing 3, 3 is active.
// Set all memory slots to be CPU memory.
POKE(MMU_MEM_BANK_0, 0);
POKE(MMU_MEM_BANK_1, 1);
POKE(MMU_MEM_BANK_2, 2);
POKE(MMU_MEM_BANK_3, 3);
POKE(MMU_MEM_BANK_4, 4);
POKE(MMU_MEM_BANK_5, 5);
// MMU_MEM_BANK_6 is always mapped to I/O.
// MMU_MEM_BANK_7 belongs to the MicroKernel.
randomSeed(0); //***TODO*** Use clock or something.
}
uint16_t randomRead(void) {
byte mmu = PEEK(MMU_IO_CTRL); // Get current MMU state.
uint16_t result;
POKE(MMU_IO_CTRL, MMU_IO_PAGE_0); // Swap I/O page 0 into bank 6.
POKE(VKY_RND_CTRL, 1); // Enable.
result = PEEKW(VKY_RNDL);
POKE(MMU_IO_CTRL, mmu); // Restore MMU state.
return result;
}
void randomSeed(uint16_t seed) {
byte mmu = PEEK(MMU_IO_CTRL); // Get current MMU state.
POKE(MMU_IO_CTRL, MMU_IO_PAGE_0); // Swap I/O page 0 into bank 6.
POKEW(VKY_SEEDL, seed);
POKE(VKY_RND_CTRL, 3); // Enable, load seed.
POKE(MMU_IO_CTRL, mmu); // Restore MMU state.
}
void waitVerticalBlank(void) {
byte mmu = PEEK(MMU_IO_CTRL); // Get current MMU state.
POKE(MMU_IO_CTRL, MMU_IO_PAGE_0); // Swap I/O page 0 into bank 6.
//***TODO*** This assumes we're 60hz with graphics enabled.
while (PEEKW(RAST_ROW_L) == 482)
// Spin our wheels.
;
while (PEEKW(RAST_ROW_L) != 482)
// Spin our wheels.
;
POKE(MMU_IO_CTRL, mmu); // Restore MMU state.
}