contrib/firmware/angie/c/include/serial.h

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 /**
   4  * This code was taken from the fx2lib project from this link:
   5  * https://github.com/djmuhlestein/fx2lib
   6  *
   7  * Copyright (C) 2009 Ubixum, Inc.
   8  **/
   9
  10 /** \file serial.h
  11  * defines functions to print to a serial console with SIO0
  12  **/
  13
  14 #include "fx2macros.h"
  15 #include <stdint.h>
  16 /**
  17  * This function inits sio0 to use T2CON (timer 2)
  18  * See TRM 14.3.4.1 (Table 14-16)
  19  * Certain baud rates have too high an error rate to work.  All baud rates are .16%
  20  * except:
  21  *
  22  *          12MHZ      24MHZ
  23  *   \li 57600  -6.99%
  24  *   \li 38400  -2.34%     -2.34%
  25  *   \li 19200  -2.34%
  26  *
  27  *   Possible Baud rates:
  28  *    \li 2400
  29  *    \li 4800
  30  *    \li 9600
  31  *    \li 19200
  32  *    \li 28800
  33  *    \li 38400
  34  *    \li 57600
  35  *
  36  *    Any of these rates should work except 57600 at 12mhz.  -2.34% is pushing
  37  *    most hardware specs for working.  All rates at 48mhz work at .16%
  38  **/
  39
  40 void sio0_init(uint32_t baud_rate) __critical; /* baud_rate max should be 57600 since int=2 bytes */
  41
  42 /**
  43  * putchar('\\n') or putchar('\\r') both transmit \\r\\n
  44  * Just use one or the other. (This makes terminal echo easy)
  45  **/
  46 int putchar(char c);
  47 int getchar(void);