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// SPDX-License-Identifier: LGPL-2.1-or-later
/*
* This code was taken from the fx2lib project from this link:
* https://github.com/djmuhlestein/fx2lib
*
* Copyright (C) 2009 Ubixum, Inc.
*/
#include <reg_ezusb.h>
#include <fx2macros.h>
#include <serial.h>
#include <stdint.h>
/**
* using the comp port implies that timer 2 will be used as
* a baud rate generator. (Don't use timer 2)
**/
void sio0_init(uint32_t baud_rate) __critical
{
uint16_t hl; /* hl value for reload */
uint8_t mult; /* multiplier for clock speed */
uint32_t tmp; /* scratch for mult/divide */
mult = (CPUFREQ == CLK_12M) ? 1 : ((CPUFREQ == CLK_24M) ? 2 : 4);
/* set the clock rate */
/* use clock 2 */
RCLK = 1; TCLK = 1;
tmp = mult * 375000L * 2;
tmp /= baud_rate;
tmp += 1;
tmp /= 2;
hl = 0xFFFF - (uint16_t)tmp;
RCAP2H = (uint8_t)(((uint16_t)(hl) >> 8) & 0xff);
/* seems that the 24/48mhz calculations are always one less than suggested values */
/* trm table 14-16 */
RCAP2L = ((uint8_t)((uint16_t)(hl) & 0xff)) + (mult > 0 ? 1 : 0);
/* start the timer */
TR2 = 1;
/* set up the serial port */
SM0 = 0; SM1 = 1; /* serial mode 1 (asyncronous) */
SM2 = 0 ; /* has to do with receiving */
REN = 1 ; /* to enable receiving */
PCON |= 0x80; /* SET SMOD0, baud rate doubler */
TI = 1; /* we send initial byte */
}
int getchar(void)
{
char c;
while (!RI)
;
c = SBUF0;
RI = 0;
return c;
}
void _transchar(char c)
{
while (!TI)
; /* wait for TI=1 */
TI = 0;
SBUF0 = c;
}
int putchar (char c)
{
if (c == '\n')
_transchar('\r'); /* transmit \r\n */
_transchar(c);
if (c == '\r')
_transchar('\n'); /* transmit \r\n */
return c;
}
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