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#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>


enum PS2_CONTROLLER
{
	PS2_DATA_PORT  = 0x60,
	PS2_STATUS_REGISTER = 0x64,
	PS2_COMMAND_REGISTER = 0x64,

	// status register
	PS2_OUTPUT_BUFFER_STATUS = 0b1,	// Must be set before reading 0x60 (0=empty, 1=full)
	PS2_INPUT_BUFFER_STATUS = 0b10,	// must be clear before writing 0x60 (0=empty, 1=full)

	//READ_BYTE = 0x20;	// response is Controller Configuration Byte
	//WRITE_BYTE = 0x60;
	// command port
	PS2_READ_CONTROLLER_OUTPUT = 0xd0,
	PS2_WRITE_CONTROLLER_OUTPUT = 0xd1,  // check if output buffer is empty first
	DISABLE_PS2_0 = 0xa7,
	ENABLE_PS2_0 = 0xa8,
	TEST_PS2_0 = 0xa9,
	TEST_PS2_CONTROLLER = 0xaa,
	TEST_PS2_1 = 0xaB,
	DISABLE_PS2_1 = 0xad,
	ENABLE_PS2_1 = 0xae,

	// device commands ? keyboard  ==> data port
	PS2_IDENTIFY_DEVICE = 0xf2,
	PS2_ENABLE_SCANNING = 0xf4,  // 0xfa=ACK, 0xfe=RESEND
	PS2_DISABLE_SCANNING = 0xf5,
	PS2_RESET_SELF_TEST = 0xff // 0xaa=pass

};

void kmain()
{
	print_char('C', 25, 79,0);

	//disable interrupts
	outb( PS2_COMMAND_REGISTER, 0x20);
	wait();
	uint8_t y = inb(0x60);
	outb( PS2_COMMAND_REGISTER,0x60);
	wait();
	outb( PS2_DATA_PORT, (y & 0b10111100) );   // disable interrups
	wait();
	
	outb( PS2_COMMAND_REGISTER, ENABLE_PS2_0 );
	wait();
	outb( PS2_COMMAND_REGISTER, ENABLE_PS2_1 );
	wait();
	outb( PS2_DATA_PORT, 0xf6 );        // set default params
	wait();
	outb( PS2_DATA_PORT, PS2_ENABLE_SCANNING );
	wait();
	outb( PS2_DATA_PORT, PS2_IDENTIFY_DEVICE );
	wait();
	print_byte(inb(PS2_DATA_PORT),20,0,1);
	wait();
	print_byte(inb(PS2_DATA_PORT),20,0,2);


	// see if key codes are being sent on port 0x60
	uint8_t volatile value;
	while (1)
	{
		wait();
		value = inb(0x60);
		print_byte(value, 25,0,0);
		wait();
	}


	asm("cli");
	while (1) { asm("hlt"); }
}

Code: Select all

outb( PS2_DATA_PORT, PS2_DISABLE_SCANNING );
wait();
outb( PS2_DATA_PORT, PS2_IDENTIFY_DEVICE );

while ( (inb ( PS2_STATUS_REGISTER ) & PS2_OUTPUT_BUFFER_STATUS) != 0b1 ) { wait(); }

Code: Select all

   
uint8_t volatile value;
uint8_t volatile i;  

outb(0x70),0;   // read seconds from 0x71
while (1)
{
      value = inb(0x71);
      print_byte(value, 20,0,0); // only prints 1 value
      print_char(i,20,3,0);  // print all the ascii - works
      i++;
}