analog/v2-analog-rev1/diag/businterface.c

#include <string.h>
#include <hardware/pio.h>
#include "common/config.h"
#include "common/buffers.h"
#include "abus.pio.h"
#include "diag/businterface.h"

static inline void __time_critical_func(shadow_memory)(uint32_t address, uint32_t value) {
    // Shadow parts of the Apple's memory by observing the bus write cycles
    if(CARD_SELECT) {
        if((value & (1u << CONFIG_PIN_APPLEBUS_RW-CONFIG_PIN_APPLEBUS_DATA_BASE)) == 0) {
            apple_memory[address] = value;
        }
        // Config memory in card slot-rom address space
        if(CARD_IOSEL) {
            if((value & (1u << CONFIG_PIN_APPLEBUS_RW-CONFIG_PIN_APPLEBUS_DATA_BASE)) == 0) {
                config_memory[address & 0x1F] = value;
                if((address & 0xFF) == 0xFF)
                    config_handler();
            }
        }
    }
}


void __time_critical_func(diag_businterface)() {
    while(v2mode == MODE_DIAG) {
        uint32_t value = pio_sm_get_blocking(CONFIG_ABUS_PIO, ABUS_MAIN_SM);
        uint32_t dout;
        uint32_t address = (value >> 10) & 0xffff;

        if((value & (1u << CONFIG_PIN_APPLEBUS_RW-CONFIG_PIN_APPLEBUS_DATA_BASE)) != 0) {
            if(CARD_SELECT) {
                dout = apple_memory[address];

                // device read access
                pio_sm_put_blocking(CONFIG_ABUS_PIO, ABUS_DEVICE_READ_SM, dout);
            }
        }

        shadow_memory(address, value);
    }
}