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use core::ptr::write_volatile;
const Z80_RAM_BASE: u32 = 0xa00000;
const Z80_RAM_SIZE: u32 = 0x2000;
const Z80_CTRL_BASE: u32 = 0xa11100;
const Z80_BUS_REQ: *mut u16 = Z80_CTRL_BASE as _;
const Z80_RESET: *mut u16 = (Z80_CTRL_BASE + 0x100) as _;
pub fn request_bus(r: bool) {
unsafe {
if r {
write_volatile(Z80_BUS_REQ, 0x100);
} else {
write_volatile(Z80_BUS_REQ, 0);
}
}
}
pub fn halt(r: bool) {
unsafe {
if r {
write_volatile(Z80_RESET, 0);
} else {
write_volatile(Z80_RESET, 0x100);
}
}
}
pub fn reset() {
request_bus(true);
halt(false);
request_bus(false);
}
pub unsafe fn ram() -> &'static mut [u8] {
core::slice::from_raw_parts_mut(Z80_RAM_BASE as _, Z80_RAM_SIZE as usize)
}