/*

FtduinoSimple.cpp - Library for ftduino

(c) 2017 by Till Harbaum <[email protected]>

A very simple io library for the ftduino only supporting

diginal IO but without and interrupt handlers and with a

small footprint.

If you need analog io, ultrasonic IO and fast counters use

the full feature version.

*/

#include "Arduino.h"

#include <avr/pgmspace.h>

#include <avr/interrupt.h>

#include "FtduinoSimple.h"

Ftduino ftduino;

void Ftduino::cd4051_init() {

// PC.6 = ING, PF.0 = A, PF1 = B, PD.5 = C

// make all 4051 control signals outputs

DDRC |= (1<<6); // INHIBIT

PORTC |= (1<<6); // pull it high by default, disabling the 4051

DDRF |= (1<<0); // A

PORTF &= ~(1<<0); // = low

DDRF |= (1<<1); // B

PORTF &= ~(1<<1); // = low

DDRD |= (1<<5); // C

PORTD &= ~(1<<5); // = low

}

void Ftduino::cd4051_set(char mode) {

// enable/disable pullup

// 0..7 = on for I1..I8, 8 = off

if(mode & 8)

PORTC |= (1<<6); // activate INH pin

else {

PORTC &= ~(1<<6); // de-activate INH pin

if(mode & 1) PORTF |= (1<<0); // A=1

else PORTF &= ~(1<<0); // A=0

if(mode & 2) PORTF |= (1<<1); // B=1

else PORTF &= ~(1<<1); // B=0

if(mode & 4) PORTD |= (1<<5); // C=1

else PORTD &= ~(1<<5); // C=0

}

}

void Ftduino::input_init() {

cd4051_init();

// the digital counterparts of ADC4-11 are distributed all over the chip

// ADC4-7 are PF.4-PF.7

DDRF &= ~((1<<7)|(1<<6)|(1<<5)|(1<<4));

// ADC8,9,10 are PD.4,PD.6 and PD.7

DDRD &= ~((1<<7)|(1<<6)|(1<<4));

// ADC11 is PB.4

DDRB &= ~(1<<4);

}

bool Ftduino::input_get(uint8_t ch) {

static char cd4051_mode = -1;

bool rval = false;

// this enables the pullup for the given channel and returns

// its digital state

// enable pullup if necessary

if(cd4051_mode != ch) {

cd4051_set(ch);

_delay_us(100);

cd4051_mode = ch;

}

switch(ch) {

case Ftduino::I1:

rval = PINF & (1<<4);

break;

case Ftduino::I2:

rval = PINF & (1<<5);

break;

case Ftduino::I3:

rval = PINF & (1<<6);

break;

case Ftduino::I4:

rval = PINF & (1<<7);

break;

case Ftduino::I5:

rval = PIND & (1<<4);

break;

case Ftduino::I6:

rval = PIND & (1<<6);

break;

case Ftduino::I7:

rval = PIND & (1<<7);

break;

case Ftduino::I8:

rval = PINB & (1<<4);

break;

}

// return true if pin is grounded

return !rval;

}

void Ftduino::output_init() {

uint8_t i;

// configure /SS, SCK and MOSI as output

// drive /SS it high

DDRB |= (1<<0) | (1<<1) | (1<<2);

PORTB |= (1<<0);

// enable SPI, no interrupts, MSB first, Master mode,

// mode 1 (SCK low when idle, data valid on falling edge)

// and clock = FCPU/16 = 1Mhz

SPCR = (1<<SPE) | (0<<DORD) | (1<<MSTR) |

(0<<CPOL) | (1<<CPHA) | (0<<SPR1) | (1<<SPR0);

SPSR &= ~(1<<SPI2X); // single speed

// PE.6 is EN. Chip is in sleep then EN == 0. EN is held low

// during and directly after reset by pull-down r31

DDRE |= (1<<6);

PORTE |= (1<<6); // not in sleep mode

// PB.7 is the PWM input of the IN6 of O2. We don't use that feature by

// now, so it's just pulled down

DDRB |= (1<<7);

PORTB &= ~(1<<7); // no PWM on IN6

spi_tx = 0; // all outputs off

output_spi_tx();

}

void Ftduino::output_spi_tx(void) {

uint8_t i;

uint32_t data = spi_tx;

// set /SS low

PORTB &= ~(1<<0);

// send four bytes (32 bit) via SPI

for(i=0;i<4;i++) {

SPDR = data & 0xff;

data >>= 8;

while(!(SPSR & (1<<SPIF)));

}

// set /SS high

PORTB |= (1<<0);

}

#define MC33879_PORT(a) (1<<(a-1))

static const uint8_t mc33879_highside_map[4] = {

MC33879_PORT(2), MC33879_PORT(6), MC33879_PORT(4), MC33879_PORT(5) };

static const uint8_t mc33879_lowside_map[4] = {

MC33879_PORT(8), MC33879_PORT(1), MC33879_PORT(7), MC33879_PORT(3) };

// any SPI transfer transfers 16 bits per mc33879 and 32 bits in total

void Ftduino::output_set(uint8_t port, uint8_t mode) {

uint32_t set_mask = 0, clr_mask = 0;

// mode can be 0 (floating), 1 (high) or 2 (low)

if(mode == 1) {

set_mask = mc33879_highside_map[port&3]; // highside to be set

clr_mask = mc33879_lowside_map[port&3]; // lowside to be cleared

} else if(mode == 2) {

set_mask = mc33879_lowside_map[port&3]; // lowside to be set

clr_mask = mc33879_highside_map[port&3]; // highside to be cleared

} else {

set_mask = 0; // nothing to be set

clr_mask = mc33879_highside_map[port&3] | // highside and lowside to be cleared

mc33879_lowside_map[port&3];

}

// ports O1..O4 (0-3) are in MSB, ports O5-O8 (4-7) are in MSB of lower 16 bit

if(port & 4) {

set_mask <<= 8;

clr_mask <<= 8;

} else {

set_mask <<= 24;

clr_mask <<= 24;

}

spi_tx |= set_mask;

spi_tx &= ~clr_mask;

output_spi_tx();

}

void Ftduino::motor_set(uint8_t port, uint8_t mode) {

// map from motor to output port

uint8_t o = (2 * (port - Ftduino::M1)) + Ftduino::O1;

switch(mode) {

case Ftduino::OFF:

// both outputs open

output_set(o , Ftduino::OFF);

output_set(o+1, Ftduino::OFF);

break;

case Ftduino::LEFT:

// both outputs driven low/hi

output_set(o , Ftduino::LO);

output_set(o+1, Ftduino::HI);

break;

case Ftduino::RIGHT:

// both outputs driven low/hi

output_set(o , Ftduino::HI);

output_set(o+1, Ftduino::LO);

break;

case Ftduino::BRAKE:

// both outputs driven low

output_set(o , Ftduino::LO);

output_set(o+1, Ftduino::LO);

break;

}

}

// control pull-down on c1 to trigger distance sensor

void Ftduino::pulldown_c1_init() {

DDRE |= (1<<2); // pulldown is controlled by PE.2 (#HWB)

PORTE &= ~(1<<2); // de-activate by default

}

void Ftduino::pulldown_c1_enable(char on) {

if(on) PORTE |= (1<<2);

else PORTE &= ~(1<<2);

}

bool Ftduino::counter_get_state(uint8_t ch) {

if(ch == Ftduino::C1) return !(PIND & (1<<2));

if(ch == Ftduino::C2) return !(PIND & (1<<3));

if(ch == Ftduino::C3) return !(PINB & (1<<5));

if(ch == Ftduino::C4) return !(PINB & (1<<6));

return false;

}

void Ftduino::counter_init(void) {

// C1/C2 are PD.2/PD.3 and C3/C4 are on PB.5/PB.6

DDRD &= ~((1 << 2) | (1 << 3)); // counter ports C1 and C2 are inputs

PORTD &= ~((1 << 2) | (1 << 3)); // disable internal pullup, we use external

DDRB &= ~((1 << 5) | (1 << 6)); // counter ports C3 and C4 are inputs

PORTB &= ~((1 << 5) | (1 << 6)); // disable internal pullup, we use external

}

Ftduino::Ftduino() {

// ---------------------------------------------------------

// prepare digital input system fot I1..I8

input_init();

// init the pulldown for the ultrasonic. However, no

// support for the sensor in the simple lib

pulldown_c1_init();

// prepare spi service for M1..M4/O1..O8

// No PWM in the simple lib

output_init();

// the simple lib only uses the counters as digital inouts

counter_init();

}