#include <c8051f040.h>
#include "sysinit.h" // for SYSCLK

//#define SYSCLK 22118400

#define BAUDRATE 57600
#define BAUDVAL (65536 - (SYSCLK / BAUDRATE / 32)) // why 32 and not 16??


void uart0_init(void) {
	char save = SFRPAGE;

	SFRPAGE = UART0_PAGE;
	SCON0 = 0x70; // enable Uart0 TX and RX, stop bit level checking
	SSTA0 = 0x15; // disable divide-by-two on baud rate, enable timer2 clock source
	TI0 = 1; // initialize transmitter ready flag

	SFRPAGE = TMR2_PAGE;

	// Load the preload value into Timer2
	RCAP2L = (BAUDVAL & 0xff);
	RCAP2H = ((BAUDVAL >> 8) & 0xff);

	// Set up Timer2
	TMR2CF = 0x08; // use SYSCLK as Timer2 timebase
	TMR2CN = 0x04; // start Timer2

	SFRPAGE = save;
}



void uart0_tx(char ch) {
	char save = SFRPAGE;
	SFRPAGE = UART0_PAGE;

	while (!TI0);
	TI0 = 0;

	SBUF1 = ch;

	SFRPAGE = save;
}

char uart0_rx(void) {
	char save = SFRPAGE;
	char ch;
	SFRPAGE = UART0_PAGE;

	while (!RI0);
	RI0 = 0;
	ch = SBUF0;

	SFRPAGE = save;
	return ch;
}

char uart0_ready(void) {
	char save = SFRPAGE;
	char ret;
	SFRPAGE = UART0_PAGE;

	ret = (RI0 != 0);

	SFRPAGE = save;
	return ret;
}

void putchar(char c) {
	uart0_tx(c);
}

char getchar(void) {
	return uart0_rx( );
}