/* Copyright 2014 Greg Stein
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// ### docco

#include <Wire.h>

#define TARGET_ADDR     10
//#define LED             9
#define LED             13


void setup(void)
{
    Serial.begin(115200);
    Wire.begin();
    pinMode(LED, OUTPUT);     
}


#define OP_ENABLE  0x20
#define OP_DISABLE 0x00

#define OP_PORTA   0x00
#define OP_PORTC   0x02

static void send_op(uint8_t enable, uint8_t port, uint8_t pin)
{
    uint8_t value = enable | port;

    switch (pin)
    {
    case 0:
        value |= 0x01;
        break;
    case 1:
        value |= 0x09;
        break;
    case 2:
        value |= 0x04;
        break;
    case 3:
        value |= 0x0C;
        break;
    case 4:
        value |= 0x10;
        break;
    case 5:
        value |= 0x18;
        break;
    }

    // WRITE to the TARGET
    Wire.beginTransmission(TARGET_ADDR);
    Wire.write(value);
    Wire.endTransmission();

    // ### check for ACK
}


void loop(void)
{
#if 0
    digitalWrite(LED, LOW);
    send_op(OP_ENABLE, OP_PORTA, 4);
    delay(500);

    digitalWrite(LED, HIGH);
    send_op(OP_DISABLE, OP_PORTA, 5);
    delay(500);

    digitalWrite(LED, LOW);
    send_op(OP_ENABLE, OP_PORTC, 1);
    delay(500);

    digitalWrite(LED, HIGH);
    send_op(OP_DISABLE, OP_PORTA, 4);
    delay(500);

    digitalWrite(LED, LOW);
    send_op(OP_ENABLE, OP_PORTC, 0);
    delay(500);

    digitalWrite(LED, HIGH);
    send_op(OP_DISABLE, OP_PORTC, 1);
    delay(500);

    digitalWrite(LED, LOW);
    send_op(OP_ENABLE, OP_PORTA, 5);
    delay(500);

    digitalWrite(LED, HIGH);
    send_op(OP_DISABLE, OP_PORTC, 0);
    delay(500);
#endif

#if 1
    digitalWrite(LED, HIGH);
    send_op(OP_ENABLE, OP_PORTA, 0);
    delay(500);

    digitalWrite(LED, LOW);
    send_op(OP_DISABLE, OP_PORTA, 0);
    delay(500);
#endif
}