/*
 *  File name:  test_cap2.c
 *  Date first: 01/08/2018
 *  Date last:  01/09/2018
 *
 *  Description: STM8 test program for capture on Timer2
 *
 *  Author:     Richard Hodges
 *
 *  Copyright (C) 2018 Richard Hodges. All rights reserved.
 *  Permission is hereby granted for any use.
 *
 ******************************************************************************
 *
 * This program tests the timer2 capture library by receiving serial bits
 * from another host and sending the capture counts back. To use this, connect
 * a TTL to USB adapter to pins 2 (TX) and 3 (RX) and power and ground. Be
 * sure to connect the USB adapter RX to STM TX and TX to RX. On the other
 * host, use a terminal program (eg, minicom) to send bytes and display the
 * capture results.
 *
 ******************************************************************************
 *
 *  Pinout:
 *
 *  Pin 1, PD4: Timer2 channel 1
 *  Pin 2, PD5: UART TX
 *  Pin 3, PD6: UART RX
 *
 *  Pins 1 and 3 connected so that RX bytes also go to Timer2 capture.
 */

#include "stm8.h"
#include "lib_uart.h"
#include "lib_cap2.h"
#include "lib_bindec.h"

void setup(void);

/******************************************************************************
 *
 *  Receive bits to UART, capture the bit lengths, print to UART TX
 */

int main() {
    char	decimal[12];
    int		count;
    char	bitct, assembled, val;

    setup();
    uart_init(BAUD_9600);
    cap2_init(CAP2_16_MHZ);

    while (1) {
	while (!uart_rsize());	/* wait for UART byte */
	while (uart_rsize()) {	/* normally only one, but use all */
	    val = uart_get();
	    uart_puts("\r\nReceived '");
	    uart_put(val);
	    uart_puts("'  0x");
	    bin8_hex(val, decimal);
	    uart_puts(decimal);
	    uart_puts("\r\n");
	}
	bitct = 0;
	assembled = 0;
	while (cap2_count()) {
	    count = cap2_get();
	    bitct++;
	    if (bitct < 2)
		continue;	/* throw away count before start bit */
	    bin16_dec(count, decimal);
	    decimal_rlz(decimal, 4);
	    uart_puts(decimal);
	    uart_put(' ');
	    count /= 1582;	/* 1666 per bit +- 5% */
	    if (bitct == 2)
		count--;	/* first sample, drop start bit */
	    while (count) {
		assembled >>= 1;
		if (bitct & 1)
		    assembled |= 0x80;
		count--;
	    }
	}
	uart_puts(" (assembled=0x");
	bin8_hex(assembled, decimal);
	uart_puts(decimal);
	uart_puts(") overflow=");
	bin16_dec(cap2_overflow(), decimal);
	uart_puts(decimal);
	uart_puts("\r\n");
    }
}

/******************************************************************************
 *
 *  Initial setup
 */

void setup(void)
{
    CLK_CKDIVR = 0;		/* clock 16mhz */

    PA_DDR = 0x00;		/* start with all inputs */
    PA_CR1 = 0xff;		/* weak pull-ups */
    PA_CR2 = 0x00;		/* no interrupts */

    PB_DDR = 0x20;		/* PB5 is LED */
    PB_CR1 = 0xff;
    PB_CR2 = 0x00;

    PC_DDR = 0x00;
    PC_CR1 = 0xff;
    PC_CR2 = 0x00;

    PD_DDR = 0x00;
    PD_CR1 = 0xef;		/* IMPORTANT: no pullup for PD4 */
    PD_CR2 = 0x00;

    __asm__ ("rim");
}