This is a simple program demonstrating how to interface with a CPSF or CPSF-MD joystick. Refer to the following page for joystick register [[joystick_regs|reference]]. Using a second CPSF should follow the same technique but with joyport_b, IOC5 and PC5. It can be compiled with the Lydux toolchain with the following commands:

<file>
$ human68k-gcc joytest.c -liocs
$ human68k-objcopy -O xfile a.out joytest.x
</file>


Code:
<file>
// This is a simple program demonstrating how to interface with a CPSF or CPSF-MD joystick
// Using a second CPSF should follow the same technique but with joyport_b, IOC4 and PC5

#include <stdint.h>
#include <stdio.h>
#include <iocslib.h>

volatile uint8_t *joyport_a = (uint8_t*)0xE9A001;
volatile uint8_t *joyport_b = (uint8_t*)0xE9A003;
volatile uint8_t *joyport_c = (uint8_t*)0xE9A005; // joy control
uint8_t *joycontrolword = (uint8_t*)0xE9A007; // if bit 7 = 0, bit manipulation. if bit 7 = 1, mode setting
uint8_t	joyport_c_old=0;

int main(int argc, char *argv[])
{
	uint16_t port1 = 0;
	uint32_t usp = 0;
	
	// clear screen
	printf("\e[2J");

	// this is working for all buttons with a CPSF or CPSF-MD
	
	usp = _iocs_b_super(0);
	// set IOC4 to 1, disables joystick 1 processing
	// preserves ADPCM settings
	joyport_c_old = *joyport_c;
	
	*joyport_c = 16|joyport_c_old;
	while(1)
	{
		port1=0;
		// move cursor to origin
		printf("\e[;0H");
		printf("CPSF Controller Tester\n");
		printf("Press ESC to quit.\n\n");
		
		// unset PC4, this is the controller clock/button group select pin
		*joycontrolword = 8;
		// read joyport a bits
		port1 |= (~*joyport_a)<<8;
		
		// set PC4
		*joycontrolword = 9;
		// read joyport a bits
		port1 |= (uint8_t)(~*joyport_a);
		
		printf("0x%04X\n", port1);
		
		// quit on ESC
		if(_dos_inpout(0xFF)==0x1B){
			*joycontrolword = 8;
			*joyport_c = joyport_c_old;
			_iocs_b_super(usp);
			return 0;
		}
	}
}
</file>