source: buchla-emu/emu/mid.c@ c5b6c90

/*
 *  Copyright (C) 2017 The Contributors
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or (at
 *  your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful, but
 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 *  General Public License for more details.
 *
 *  A copy of the GNU General Public License can be found in the file
 *  "gpl.txt" in the top directory of this repository.
 */

#include <all.h>

#define ver(...) _ver(mid_verbose, 0, __VA_ARGS__)
#define ver2(...) _ver(mid_verbose, 1, __VA_ARGS__)
#define ver3(...) _ver(mid_verbose, 2, __VA_ARGS__)

int32_t mid_verbose = 0;

#define REG_IER_ISR 0
#define REG_CFR_SR  1
#define REG_CDR_TBR 2
#define REG_TDR_RDR 3

void mid_init(void)
{
        ver("mid init");
}

void mid_quit(void)
{
        ver("mid quit");
}

bool mid_exec(void)
{
        ver3("mid exec");
        return false;
}

uint32_t mid_read(uint32_t off, int32_t sz)
{
        ver2("mid rd %u:%d", off, sz * 8);
        return 0;
}

void mid_write(uint32_t off, int32_t sz, uint32_t val)
{
        ver2("mid wr %u:%d 0x%0*x", off, sz * 8, sz * 2, val);

        if (sz != 1 || off > 7) {
                fail("invalid mid wr %u:%d", off, sz * 8);
        }

        int32_t rg = (int32_t)(off % 4);
        int32_t un = (int32_t)(off / 4);

        switch (rg) {
        case REG_CFR_SR:
                ver2("CFR[%d] 0x%02x", un, val);

                if (un == 1) {
                        fdd_set_side((int32_t)val & 0x01);
                }
                else {
                        fdd_set_sel((int32_t)val & 0x01);
                }

                break;

        default:
                break;
        }
}