circuitpython/pic16bit/board.c
Damien George 43ea73faa6 pic16bit: Initial version of port to 16-bit PIC family.
Reference MCU is dsPIC33J256GP506 with 256k ROM and 8k RAM, on the dsPIC
DSC Starter Kit board.  The REPL works, GC works, pyb module has LED and
Switch objects.  It passes some tests from the test suite (most it can't
run because it doesn't have the Python features enabled).
2015-04-03 14:11:19 +01:00

154 lines
3.9 KiB
C

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2015 Damien P. George
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <p33Fxxxx.h>
#include "board.h"
/********************************************************************/
// CPU
void cpu_init(void) {
// set oscillator to operate at 40MHz
// Fosc = Fin*M/(N1*N2), Fcy = Fosc/2
// Fosc = 7.37M*40/(2*2) = 80Mhz for 7.37M input clock
PLLFBD = 41; // M=39
CLKDIVbits.PLLPOST = 0; // N1=2
CLKDIVbits.PLLPRE = 0; // N2=2
OSCTUN = 0;
// initiate clock switch to FRC with PLL
__builtin_write_OSCCONH(0x01);
__builtin_write_OSCCONL(0x01);
// wait for clock switch to occur
while (OSCCONbits.COSC != 0x01) {
}
while (!OSCCONbits.LOCK) {
}
}
/********************************************************************/
// LEDs
#define RED_LED_TRIS _TRISC15
#define YELLOW_LED_TRIS _TRISC13
#define GREEN_LED_TRIS _TRISC14
#define RED_LED _LATC15
#define YELLOW_LED _LATC13
#define GREEN_LED _LATC14
#define LED_ON (0)
#define LED_OFF (1)
void led_init(void) {
// set led GPIO as outputs
RED_LED_TRIS = 0;
YELLOW_LED_TRIS = 0;
GREEN_LED_TRIS = 0;
// turn off the LEDs
RED_LED = LED_OFF;
YELLOW_LED = LED_OFF;
GREEN_LED = LED_OFF;
}
void led_state(int led, int state) {
int val = state ? LED_ON : LED_OFF;
switch (led) {
case 1: RED_LED = val; break;
case 2: YELLOW_LED = val; break;
case 3: GREEN_LED = val; break;
}
}
void led_toggle(int led) {
switch (led) {
case 1: RED_LED ^= 1; break;
case 2: YELLOW_LED ^= 1; break;
case 3: GREEN_LED ^= 1; break;
}
}
/********************************************************************/
// switches
#define SWITCH_S1_TRIS _TRISD8
#define SWITCH_S2_TRIS _TRISD9
#define SWITCH_S1 _RD8
#define SWITCH_S2 _RD9
void switch_init(void) {
// set switch GPIO as inputs
SWITCH_S1_TRIS = 1;
SWITCH_S2_TRIS = 1;
}
int switch_get(int sw) {
int val = 1;
switch (sw) {
case 1: val = SWITCH_S1; break;
case 2: val = SWITCH_S2; break;
}
return val == 0;
}
/********************************************************************/
// UART
/*
// TODO need an irq
void uart_rx_irq(void) {
if (c == interrupt_char) {
MP_STATE_VM(mp_pending_exception) = MP_STATE_PORT(keyboard_interrupt_obj);
}
}
*/
void uart_init(void) {
// baudrate = F_CY / 16 (uxbrg + 1)
// F_CY = 40MHz for us
UART1.uxbrg = 64; // 38400 baud
UART1.uxmode = 1 << 15; // UARTEN
UART1.uxsta = 1 << 10; // UTXEN
}
int uart_rx_any(void) {
return UART1.uxsta & 1; // URXDA
}
int uart_rx_char(void) {
return UART1.uxrxreg;
}
void uart_tx_char(int chr) {
while (UART1.uxsta & (1 << 9)) {
// tx fifo is full
}
UART1.uxtxreg = chr;
}