riscv-openocd/contrib/firmware/angie/c/include/serial.h

48 lines
1.2 KiB
C

/* 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.
**/
/** \file serial.h
* defines functions to print to a serial console with SIO0
**/
#include "fx2macros.h"
#include <stdint.h>
/**
* This function inits sio0 to use T2CON (timer 2)
* See TRM 14.3.4.1 (Table 14-16)
* Certain baud rates have too high an error rate to work. All baud rates are .16%
* except:
*
* 12MHZ 24MHZ
* \li 57600 -6.99%
* \li 38400 -2.34% -2.34%
* \li 19200 -2.34%
*
* Possible Baud rates:
* \li 2400
* \li 4800
* \li 9600
* \li 19200
* \li 28800
* \li 38400
* \li 57600
*
* Any of these rates should work except 57600 at 12mhz. -2.34% is pushing
* most hardware specs for working. All rates at 48mhz work at .16%
**/
void sio0_init(uint32_t baud_rate) __critical; /* baud_rate max should be 57600 since int=2 bytes */
/**
* putchar('\\n') or putchar('\\r') both transmit \\r\\n
* Just use one or the other. (This makes terminal echo easy)
**/
int putchar(char c);
int getchar(void);