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Use PlatformIO for firmware

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This commit is contained in:
Andrew Kay
2020-03-28 10:33:40 -05:00
parent 543453c364
commit 9aed726452
7 changed files with 547 additions and 526 deletions
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1
interface1/firmware/.gitignore vendored Normal file
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.pio

303
interface1/firmware/CoaxTransceiver.cpp
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// Copyright (c) 2019, Andrew Kay
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#include <Arduino.h>
#include "CoaxTransceiver.h"
// Arduino Mega pins...
//
// Arduino Arduino Port Label DP8340N DP8341N
// Pin and Mask Pin Pin
// ---------|--------------|-----------------|---------|---------
// 7 | | EVEN/ODD PARITY | 18 |
// 6 | PH3 0x08 | PARITY CONTROL | 19 |
// 5 | | AUTO RESPONSE | 21 |
// 4 | PG5 0x20 | REGISTERS FULL | 22 |
// 3 | PE5 0x20 | REGISTER LOAD | 23 |
// ---------.--------------.-----------------.---------.---------
// 2 | | DATA CONTROL | | 5
// 14 | PJ1 0x02 | ERROR | | 8
// 15 | PJ0 0x01 | DATA AVAILABLE | | 10
// 16 | PH1 0x02 | REGISTER READ | | 9
// 17 | PH0 0x01 | OUTPUT CONTROL | | 11
// 18* | PD3 0x08 | RECEIVER ACTIVE | | 7
// 19 | PD2 0x04 | OUTPUT ENABLE | | 13
// ---------.--------------.-----------------.---------.---------
// 22 | PA0 | D11 | 1 | 23
// 23 | PA1 | D10 | 2 | 22
// 24 | PA2 | D9 | 3 | 21
// 25 | PA3 | D8 | 4 | 20
// 26 | PA4 | D7 | 5 | 19
// 27 | PA5 | D6 | 6 | 18
// 28 | PA6 | D5 | 7 | 17
// 29 | PA7 | D4 | 8 | 16
// 36 | PC1 | D2 | 10 | 14
// 37 | PC0 | D3 | 9 | 15
//
// * - Interrupt capable pin
#define TX_EVEN_ODD_PARITY_PIN 7
#define TX_PARITY_CONTROL_PIN 6
#define TX_AUTO_RESPONSE_PIN 5
#define TX_REGISTERS_FULL_PIN 4
#define TX_REGISTER_LOAD_PIN 3
#define RX_DATA_CONTROL_PIN 2
#define RX_ERROR_PIN 14
#define RX_DATA_AVAILABLE_PIN 15
#define RX_REGISTER_READ_PIN 16
#define RX_OUTPUT_CONTROL_PIN 17
#define RX_ACTIVE_PIN 18
#define RX_OUTPUT_ENABLE_PIN 19
#define RX_STATE_DISABLED 0
#define RX_STATE_WAITING 1
#define RX_STATE_RECEIVING 2
#define RX_STATE_RECEIVED 3
static volatile uint8_t CoaxTransceiver::rxState;
static volatile uint16_t *CoaxTransceiver::rxBuffer;
static volatile size_t CoaxTransceiver::rxBufferSize;
static volatile int /* ssize_t */ CoaxTransceiver::rxBufferCount;
#define NOP __asm__("nop\n\t")
static void CoaxTransceiver::setup() {
// Configure data bus.
dataBusSetup();
// Configure receiver (DP8341N).
rxSetup();
// Configure transmitter (DP8340N).
txSetup();
}
static int /* ssize_t */ CoaxTransceiver::transmitReceive(uint16_t *transmitBuffer, size_t transmitBufferCount, uint16_t *receiveBuffer, size_t receiveBufferSize, uint16_t receiveTimeout) {
int returnValue = transmit(transmitBuffer, transmitBufferCount);
if (returnValue < 0) {
return returnValue;
}
return receive(receiveBuffer, receiveBufferSize, receiveTimeout);
}
static void CoaxTransceiver::dataBusSetup() {
DDRA = B00000000;
DDRC = B00000000;
}
static void CoaxTransceiver::rxSetup() {
// Data Control - Amplifier Inputs
pinMode(RX_DATA_CONTROL_PIN, OUTPUT);
digitalWrite(RX_DATA_CONTROL_PIN, HIGH);
// Register Read
pinMode(RX_REGISTER_READ_PIN, OUTPUT);
digitalWrite(RX_REGISTER_READ_PIN, HIGH);
// Output Control - Data
pinMode(RX_OUTPUT_CONTROL_PIN, OUTPUT);
digitalWrite(RX_OUTPUT_CONTROL_PIN, HIGH);
// Output Enable - Active
pinMode(RX_OUTPUT_ENABLE_PIN, OUTPUT);
digitalWrite(RX_OUTPUT_ENABLE_PIN, HIGH);
// Receiver Active
pinMode(RX_ACTIVE_PIN, INPUT);
attachInterrupt(digitalPinToInterrupt(RX_ACTIVE_PIN), rxActiveInterrupt, RISING);
// Data Available
pinMode(RX_DATA_AVAILABLE_PIN, INPUT);
// Error
pinMode(RX_ERROR_PIN, INPUT);
}
static void CoaxTransceiver::txSetup() {
// Register Load
pinMode(TX_REGISTER_LOAD_PIN, OUTPUT);
digitalWrite(TX_REGISTER_LOAD_PIN, HIGH);
// Auto Response - Data
pinMode(TX_AUTO_RESPONSE_PIN, OUTPUT);
digitalWrite(TX_AUTO_RESPONSE_PIN, HIGH);
// Even/Odd Parity - Even
pinMode(TX_EVEN_ODD_PARITY_PIN, OUTPUT);
digitalWrite(TX_EVEN_ODD_PARITY_PIN, HIGH);
// Parity Control - Data
pinMode(TX_PARITY_CONTROL_PIN, OUTPUT);
digitalWrite(TX_PARITY_CONTROL_PIN, HIGH);
// Registers Full
pinMode(TX_REGISTERS_FULL_PIN, INPUT);
}
static int /* ssize_t */ CoaxTransceiver::transmit(uint16_t *buffer, size_t bufferCount) {
// Ensure receiver is inactive.
if (rxState != RX_STATE_DISABLED) {
return ERROR_TX_RECEIVER_ACTIVE;
}
if (/* RECEIVER ACTIVE */ (PIND & 0x8) == 0x8) {
return ERROR_TX_RECEIVER_ACTIVE;
}
// Disable interrupts.
noInterrupts();
// Disable receiver output.
PORTD &= ~0x04; // RX Output Enable - Low (Disable)
// Configure data bus for output.
DDRA = B11111111;
DDRC = B00000011;
// Transmit.
for (int index = 0; index < bufferCount; index++) {
uint16_t data = buffer[index];
// Wait while TX Registers Full is high.
while ((PING & 0x20) == 0x20) {
NOP;
}
PORTC = (PINC & 0xfc) | ((data >> 8) & 0x3);
PORTA = data & 0xff;
PORTE &= ~0x20; // TX Register Load - Low (Load)
PORTE |= 0x20; // TX Register Load - High
}
// Configure data bus for input.
DDRA = B00000000;
DDRC = B00000000;
// Enable receiver output.
PORTD |= 0x04; // RX Output Enable - High (Enable)
// Enable interrupts.
interrupts();
return bufferCount;
}
static int /* ssize_t */ CoaxTransceiver::receive(uint16_t *buffer, size_t bufferSize, uint16_t timeout) {
rxBuffer = buffer;
rxBufferSize = bufferSize;
rxState = RX_STATE_WAITING;
if (timeout > 0) {
unsigned long startTime = millis();
while (rxState == RX_STATE_WAITING) {
// https://www.forward.com.au/pfod/ArduinoProgramming/TimingDelaysInArduino.html#unsigned
if ((millis() - startTime) > timeout) {
rxState = RX_STATE_DISABLED;
return ERROR_RX_TIMEOUT;
}
}
}
while (rxState != RX_STATE_RECEIVED) {
NOP;
}
uint16_t count = rxBufferCount;
rxState = RX_STATE_DISABLED;
if (count < 0) {
return count;
}
// Check for receiver errors.
for (int index = 0; index < count; index++) {
if (buffer[index] & 0x8000) {
return ERROR_RX_RECEIVER;
}
}
return count;
}
static void CoaxTransceiver::rxActiveInterrupt() {
uint16_t data;
uint8_t mask;
if (rxState == RX_STATE_DISABLED) {
return;
}
rxState = RX_STATE_RECEIVING;
rxBufferCount = 0;
do {
while (/* ERROR or DATA AVAILABLE */ (PINJ & 0x03) == 0) {
NOP;
}
if (/* ERROR */ (PINJ & 0x02) == 0x02) {
mask = 0x02;
PORTH &= ~0x01; // Output Control - Low (Error)
PORTH &= ~0x02; // Register Read - Low
// Read and mark as error.
data = (((PINC & 0x3) | 0x80) << 8) | PINA;
PORTH |= 0x02; // Register Read - High
PORTH |= 0x01; // Output Control - High (Data)
} else if (/* DATA AVAILABLE */ (PINJ & 0x01) == 0x01) {
mask = 0x01;
PORTH &= ~0x02; // Register Read - Low
// Read.
data = ((PINC & 0x3) << 8) | PINA;
PORTH |= 0x02; // Register Read - High
}
if (rxBufferCount >= rxBufferSize) {
rxBufferCount = ERROR_RX_OVERFLOW;
goto EXIT;
}
rxBuffer[rxBufferCount++] = data;
while ((PINJ & mask) == mask) {
NOP;
}
} while (/* RECEIVER ACTIVE */ (PIND & 0x8) == 0x8);
EXIT:
rxState = RX_STATE_RECEIVED;
}

218
interface1/firmware/firmware.ino
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// Copyright (c) 2019, Andrew Kay
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#include <Arduino.h>
#include "CoaxTransceiver.h"
#define COMMAND_RESET 0x01
#define COMMAND_TRANSMIT 0x02
#define COMMAND_RECEIVE 0x04
#define COMMAND_TRANSMIT_RECEIVE 0x06
#define ERROR_INVALID_MESSAGE 1
#define ERROR_UNKNOWN_COMMAND 2
void handleResetCommand(uint8_t *buffer, int bufferCount) {
uint8_t response[] = { 0x01, 0x00, 0x00, 0x01 };
sendMessage(response, 4);
}
void handleTransmitReceiveCommand(uint8_t *buffer, int bufferCount) {
if (bufferCount < 6) {
sendErrorMessage(ERROR_INVALID_MESSAGE);
return;
}
uint16_t *transmitBuffer = (uint16_t *) (buffer + 2);
uint16_t transmitBufferCount = (bufferCount - 6) / 2;
uint16_t transmitRepeatCount = ((buffer[0] << 8) | buffer[1]) & 0x7fff;
uint16_t transmitRepeatOffset = buffer[0] >> 7;
uint16_t receiveBufferSize = (buffer[bufferCount - 4] << 8) | buffer[bufferCount - 3];
uint16_t receiveTimeout = (buffer[bufferCount - 2] << 8) | buffer[bufferCount - 1];
if (transmitBufferCount < 1) {
sendErrorMessage(ERROR_INVALID_MESSAGE);
return;
}
// Expand the provided data if applicable.
if (transmitRepeatCount > 1) {
uint8_t *source = ((uint8_t *) transmitBuffer) + (transmitRepeatOffset * 2);
uint8_t *destination = ((uint8_t *) transmitBuffer) + (transmitBufferCount * 2);
uint16_t sourceCount = transmitBufferCount - transmitRepeatOffset;
size_t length = sourceCount * 2;
for (int index = 1; index < transmitRepeatCount; index++) {
memcpy(destination, source, length);
transmitBufferCount += sourceCount;
destination += length;
}
}
uint16_t *receiveBuffer = (uint16_t *) (buffer + 2);
bufferCount = CoaxTransceiver::transmitReceive(transmitBuffer, transmitBufferCount, receiveBuffer, receiveBufferSize, receiveTimeout);
if (bufferCount < 0) {
sendErrorMessage(100 + ((-1) * bufferCount));
return;
}
// Send the response message.
buffer[1] = 0x01;
bufferCount = 1 + (bufferCount * 2);
sendMessage(buffer + 1, bufferCount);
}
void handleMessage(uint8_t *buffer, int bufferCount) {
if (bufferCount < 1) {
sendErrorMessage(ERROR_INVALID_MESSAGE);
return;
}
uint8_t command = buffer[0];
if (command == COMMAND_RESET) {
handleResetCommand(buffer + 1, bufferCount - 1);
} else if (command == COMMAND_TRANSMIT_RECEIVE) {
handleTransmitReceiveCommand(buffer + 1, bufferCount - 1);
} else {
sendErrorMessage(ERROR_UNKNOWN_COMMAND);
}
}
#define FRAME_END 0xc0
#define FRAME_ESCAPE 0xdb
#define FRAME_ESCAPE_END 0xdc
#define FRAME_ESCAPE_ESCAPE 0xdd
enum {
WAIT_START,
DATA,
ESCAPE
} frameState;
#define FRAME_BUFFER_SIZE ((25 * 80) * 2) + 32
uint8_t frameBuffer[FRAME_BUFFER_SIZE];
int frameBufferCount = 0;
void handleFrame(uint8_t *buffer, int bufferCount) {
if (bufferCount < 4) {
sendErrorMessage(ERROR_INVALID_MESSAGE);
return;
}
int count = (buffer[0] << 8) | buffer[1];
if (bufferCount - 4 != count) {
sendErrorMessage(ERROR_INVALID_MESSAGE);
return;
}
handleMessage(buffer + 2, count);
}
void sendMessage(uint8_t *buffer, int bufferCount) {
Serial.write((char) FRAME_END);
// Write the length.
Serial.write((char) bufferCount >> 8);
Serial.write((char) bufferCount);
for (int index = 0; index < bufferCount; index++) {
if (buffer[index] == FRAME_END) {
Serial.write((char) FRAME_ESCAPE);
Serial.write((char) FRAME_ESCAPE_END);
} else if (buffer[index] == FRAME_ESCAPE) {
Serial.write((char) FRAME_ESCAPE);
Serial.write((char) FRAME_ESCAPE_ESCAPE);
} else {
Serial.write((char) buffer[index]);
}
}
// Write the placeholder for checksum.
Serial.write((char) 0x00);
Serial.write((char) 0x00);
Serial.write((char) FRAME_END);
Serial.flush();
}
void sendErrorMessage(uint8_t code) {
uint8_t message[] = { 0x02, code };
sendMessage(message, 2);
}
void setup() {
// Configure serial port and state machine.
Serial.begin(115200);
frameState = WAIT_START;
while (Serial.available() > 0) {
Serial.read();
}
// Configure the transceiver.
CoaxTransceiver::setup();
}
void loop() {
if (Serial.available() > 0) {
uint8_t byte = Serial.read();
if (frameState == WAIT_START) {
if (byte == FRAME_END) {
frameState = DATA;
}
} else if (frameState == DATA) {
if (byte == FRAME_END) {
if (frameBufferCount > 0) {
handleFrame(frameBuffer, frameBufferCount);
}
frameBufferCount = 0;
} else if (byte == FRAME_ESCAPE) {
frameState = ESCAPE;
} else {
// TODO: overflow...
frameBuffer[frameBufferCount++] = byte;
}
} else if (frameState == ESCAPE) {
if (byte == FRAME_ESCAPE_END) {
// TODO: overflow...
frameBuffer[frameBufferCount++] = FRAME_END;
} else if (byte == FRAME_ESCAPE_ESCAPE) {
// TODO: overflow...
frameBuffer[frameBufferCount++] = FRAME_ESCAPE;
}
frameState = DATA;
}
}
}

8
interface1/firmware/CoaxTransceiver.h → interface1/firmware/include/CoaxTransceiver.h
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@@ -14,19 +14,17 @@
#pragma once
#include <Arduino.h>
#define ERROR_TX_RECEIVER_ACTIVE -1
#define ERROR_RX_TIMEOUT -2
#define ERROR_RX_OVERFLOW -3
#define ERROR_RX_RECEIVER -4
class CoaxTransceiver {
public:
public:
static void setup();
static int /* ssize_t */ transmitReceive(uint16_t *transmitBuffer, size_t transmitBufferCount, uint16_t *receiveBuffer, size_t receiveBufferSize, uint16_t receiveTimeout);
private:
private:
static void dataBusSetup();
static void rxSetup();
static void txSetup();

6
interface1/firmware/platformio.ini Normal file
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[env]
framework = arduino
[env:megaatmega2560]
platform = atmelavr
board = megaatmega2560

311
interface1/firmware/src/CoaxTransceiver.cpp Normal file
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// Copyright (c) 2019, Andrew Kay
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#include <Arduino.h>
#include "CoaxTransceiver.h"
// Arduino Mega pins...
//
// Arduino Arduino Port Label DP8340N DP8341N
// Pin and Mask Pin Pin
// ---------|--------------|-----------------|---------|---------
// 7 | | EVEN/ODD PARITY | 18 |
// 6 | PH3 0x08 | PARITY CONTROL | 19 |
// 5 | | AUTO RESPONSE | 21 |
// 4 | PG5 0x20 | REGISTERS FULL | 22 |
// 3 | PE5 0x20 | REGISTER LOAD | 23 |
// ---------.--------------.-----------------.---------.---------
// 2 | | DATA CONTROL | | 5
// 14 | PJ1 0x02 | ERROR | | 8
// 15 | PJ0 0x01 | DATA AVAILABLE | | 10
// 16 | PH1 0x02 | REGISTER READ | | 9
// 17 | PH0 0x01 | OUTPUT CONTROL | | 11
// 18* | PD3 0x08 | RECEIVER ACTIVE | | 7
// 19 | PD2 0x04 | OUTPUT ENABLE | | 13
// ---------.--------------.-----------------.---------.---------
// 22 | PA0 | D11 | 1 | 23
// 23 | PA1 | D10 | 2 | 22
// 24 | PA2 | D9 | 3 | 21
// 25 | PA3 | D8 | 4 | 20
// 26 | PA4 | D7 | 5 | 19
// 27 | PA5 | D6 | 6 | 18
// 28 | PA6 | D5 | 7 | 17
// 29 | PA7 | D4 | 8 | 16
// 36 | PC1 | D2 | 10 | 14
// 37 | PC0 | D3 | 9 | 15
//
// * - Interrupt capable pin
#define TX_EVEN_ODD_PARITY_PIN 7
#define TX_PARITY_CONTROL_PIN 6
#define TX_AUTO_RESPONSE_PIN 5
#define TX_REGISTERS_FULL_PIN 4
#define TX_REGISTER_LOAD_PIN 3
#define RX_DATA_CONTROL_PIN 2
#define RX_ERROR_PIN 14
#define RX_DATA_AVAILABLE_PIN 15
#define RX_REGISTER_READ_PIN 16
#define RX_OUTPUT_CONTROL_PIN 17
#define RX_ACTIVE_PIN 18
#define RX_OUTPUT_ENABLE_PIN 19
#define RX_STATE_DISABLED 0
#define RX_STATE_WAITING 1
#define RX_STATE_RECEIVING 2
#define RX_STATE_RECEIVED 3
volatile uint8_t CoaxTransceiver::rxState;
volatile uint16_t *CoaxTransceiver::rxBuffer;
volatile size_t CoaxTransceiver::rxBufferSize;
volatile int /* ssize_t */ CoaxTransceiver::rxBufferCount;
#define NOP __asm__("nop\n\t")
void CoaxTransceiver::setup()
{
// Configure data bus.
dataBusSetup();
// Configure receiver (DP8341N).
rxSetup();
// Configure transmitter (DP8340N).
txSetup();
}
int /* ssize_t */ CoaxTransceiver::transmitReceive(uint16_t *transmitBuffer, size_t transmitBufferCount, uint16_t *receiveBuffer, size_t receiveBufferSize, uint16_t receiveTimeout)
{
int returnValue = transmit(transmitBuffer, transmitBufferCount);
if (returnValue < 0) {
return returnValue;
}
return receive(receiveBuffer, receiveBufferSize, receiveTimeout);
}
void CoaxTransceiver::dataBusSetup()
{
DDRA = B00000000;
DDRC = B00000000;
}
void CoaxTransceiver::rxSetup()
{
// Data Control - Amplifier Inputs
pinMode(RX_DATA_CONTROL_PIN, OUTPUT);
digitalWrite(RX_DATA_CONTROL_PIN, HIGH);
// Register Read
pinMode(RX_REGISTER_READ_PIN, OUTPUT);
digitalWrite(RX_REGISTER_READ_PIN, HIGH);
// Output Control - Data
pinMode(RX_OUTPUT_CONTROL_PIN, OUTPUT);
digitalWrite(RX_OUTPUT_CONTROL_PIN, HIGH);
// Output Enable - Active
pinMode(RX_OUTPUT_ENABLE_PIN, OUTPUT);
digitalWrite(RX_OUTPUT_ENABLE_PIN, HIGH);
// Receiver Active
pinMode(RX_ACTIVE_PIN, INPUT);
attachInterrupt(digitalPinToInterrupt(RX_ACTIVE_PIN), rxActiveInterrupt, RISING);
// Data Available
pinMode(RX_DATA_AVAILABLE_PIN, INPUT);
// Error
pinMode(RX_ERROR_PIN, INPUT);
}
void CoaxTransceiver::txSetup()
{
// Register Load
pinMode(TX_REGISTER_LOAD_PIN, OUTPUT);
digitalWrite(TX_REGISTER_LOAD_PIN, HIGH);
// Auto Response - Data
pinMode(TX_AUTO_RESPONSE_PIN, OUTPUT);
digitalWrite(TX_AUTO_RESPONSE_PIN, HIGH);
// Even/Odd Parity - Even
pinMode(TX_EVEN_ODD_PARITY_PIN, OUTPUT);
digitalWrite(TX_EVEN_ODD_PARITY_PIN, HIGH);
// Parity Control - Data
pinMode(TX_PARITY_CONTROL_PIN, OUTPUT);
digitalWrite(TX_PARITY_CONTROL_PIN, HIGH);
// Registers Full
pinMode(TX_REGISTERS_FULL_PIN, INPUT);
}
int /* ssize_t */ CoaxTransceiver::transmit(uint16_t *buffer, size_t bufferCount)
{
// Ensure receiver is inactive.
if (rxState != RX_STATE_DISABLED) {
return ERROR_TX_RECEIVER_ACTIVE;
}
if (/* RECEIVER ACTIVE */ (PIND & 0x8) == 0x8) {
return ERROR_TX_RECEIVER_ACTIVE;
}
// Disable interrupts.
noInterrupts();
// Disable receiver output.
PORTD &= ~0x04; // RX Output Enable - Low (Disable)
// Configure data bus for output.
DDRA = B11111111;
DDRC = B00000011;
// Transmit.
for (int index = 0; index < bufferCount; index++) {
uint16_t data = buffer[index];
// Wait while TX Registers Full is high.
while ((PING & 0x20) == 0x20) {
NOP;
}
PORTC = (PINC & 0xfc) | ((data >> 8) & 0x3);
PORTA = data & 0xff;
PORTE &= ~0x20; // TX Register Load - Low (Load)
PORTE |= 0x20; // TX Register Load - High
}
// Configure data bus for input.
DDRA = B00000000;
DDRC = B00000000;
// Enable receiver output.
PORTD |= 0x04; // RX Output Enable - High (Enable)
// Enable interrupts.
interrupts();
return bufferCount;
}
int /* ssize_t */ CoaxTransceiver::receive(uint16_t *buffer, size_t bufferSize, uint16_t timeout)
{
rxBuffer = buffer;
rxBufferSize = bufferSize;
rxState = RX_STATE_WAITING;
if (timeout > 0) {
unsigned long startTime = millis();
while (rxState == RX_STATE_WAITING) {
// https://www.forward.com.au/pfod/ArduinoProgramming/TimingDelaysInArduino.html#unsigned
if ((millis() - startTime) > timeout) {
rxState = RX_STATE_DISABLED;
return ERROR_RX_TIMEOUT;
}
}
}
while (rxState != RX_STATE_RECEIVED) {
NOP;
}
uint16_t count = rxBufferCount;
rxState = RX_STATE_DISABLED;
if (count < 0) {
return count;
}
// Check for receiver errors.
for (int index = 0; index < count; index++) {
if (buffer[index] & 0x8000) {
return ERROR_RX_RECEIVER;
}
}
return count;
}
void CoaxTransceiver::rxActiveInterrupt()
{
uint16_t data;
uint8_t mask;
if (rxState == RX_STATE_DISABLED) {
return;
}
rxState = RX_STATE_RECEIVING;
rxBufferCount = 0;
do {
while (/* ERROR or DATA AVAILABLE */ (PINJ & 0x03) == 0) {
NOP;
}
if (/* ERROR */ (PINJ & 0x02) == 0x02) {
mask = 0x02;
PORTH &= ~0x01; // Output Control - Low (Error)
PORTH &= ~0x02; // Register Read - Low
// Read and mark as error.
data = (((PINC & 0x3) | 0x80) << 8) | PINA;
PORTH |= 0x02; // Register Read - High
PORTH |= 0x01; // Output Control - High (Data)
} else if (/* DATA AVAILABLE */ (PINJ & 0x01) == 0x01) {
mask = 0x01;
PORTH &= ~0x02; // Register Read - Low
// Read.
data = ((PINC & 0x3) << 8) | PINA;
PORTH |= 0x02; // Register Read - High
}
if (rxBufferCount >= rxBufferSize) {
rxBufferCount = ERROR_RX_OVERFLOW;
goto EXIT;
}
rxBuffer[rxBufferCount++] = data;
while ((PINJ & mask) == mask) {
NOP;
}
} while (/* RECEIVER ACTIVE */ (PIND & 0x8) == 0x8);
EXIT:
rxState = RX_STATE_RECEIVED;
}

226
interface1/firmware/src/main.cpp Normal file
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// Copyright (c) 2019, Andrew Kay
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#include <Arduino.h>
#include "CoaxTransceiver.h"
#define FRAME_END 0xc0
#define FRAME_ESCAPE 0xdb
#define FRAME_ESCAPE_END 0xdc
#define FRAME_ESCAPE_ESCAPE 0xdd
enum {
WAIT_START,
DATA,
ESCAPE
} frameState;
#define FRAME_BUFFER_SIZE ((25 * 80) * 2) + 32
uint8_t frameBuffer[FRAME_BUFFER_SIZE];
int frameBufferCount = 0;
#define ERROR_INVALID_MESSAGE 1
#define ERROR_UNKNOWN_COMMAND 2
void sendMessage(uint8_t *buffer, int bufferCount)
{
Serial.write((char) FRAME_END);
// Write the length.
Serial.write((char) bufferCount >> 8);
Serial.write((char) bufferCount);
for (int index = 0; index < bufferCount; index++) {
if (buffer[index] == FRAME_END) {
Serial.write((char) FRAME_ESCAPE);
Serial.write((char) FRAME_ESCAPE_END);
} else if (buffer[index] == FRAME_ESCAPE) {
Serial.write((char) FRAME_ESCAPE);
Serial.write((char) FRAME_ESCAPE_ESCAPE);
} else {
Serial.write((char) buffer[index]);
}
}
// Write the placeholder for checksum.
Serial.write((char) 0x00);
Serial.write((char) 0x00);
Serial.write((char) FRAME_END);
Serial.flush();
}
void sendErrorMessage(uint8_t code)
{
uint8_t message[] = { 0x02, code };
sendMessage(message, 2);
}
#define COMMAND_RESET 0x01
#define COMMAND_TRANSMIT 0x02
#define COMMAND_RECEIVE 0x04
#define COMMAND_TRANSMIT_RECEIVE 0x06
void handleResetCommand(uint8_t *buffer, int bufferCount)
{
uint8_t response[] = { 0x01, 0x00, 0x00, 0x01 };
sendMessage(response, 4);
}
void handleTransmitReceiveCommand(uint8_t *buffer, int bufferCount)
{
if (bufferCount < 6) {
sendErrorMessage(ERROR_INVALID_MESSAGE);
return;
}
uint16_t *transmitBuffer = (uint16_t *) (buffer + 2);
uint16_t transmitBufferCount = (bufferCount - 6) / 2;
uint16_t transmitRepeatCount = ((buffer[0] << 8) | buffer[1]) & 0x7fff;
uint16_t transmitRepeatOffset = buffer[0] >> 7;
uint16_t receiveBufferSize = (buffer[bufferCount - 4] << 8) | buffer[bufferCount - 3];
uint16_t receiveTimeout = (buffer[bufferCount - 2] << 8) | buffer[bufferCount - 1];
if (transmitBufferCount < 1) {
sendErrorMessage(ERROR_INVALID_MESSAGE);
return;
}
// Expand the provided data if applicable.
if (transmitRepeatCount > 1) {
uint8_t *source = ((uint8_t *) transmitBuffer) + (transmitRepeatOffset * 2);
uint8_t *destination = ((uint8_t *) transmitBuffer) + (transmitBufferCount * 2);
uint16_t sourceCount = transmitBufferCount - transmitRepeatOffset;
size_t length = sourceCount * 2;
for (int index = 1; index < transmitRepeatCount; index++) {
memcpy(destination, source, length);
transmitBufferCount += sourceCount;
destination += length;
}
}
uint16_t *receiveBuffer = (uint16_t *) (buffer + 2);
bufferCount = CoaxTransceiver::transmitReceive(transmitBuffer, transmitBufferCount, receiveBuffer, receiveBufferSize, receiveTimeout);
if (bufferCount < 0) {
sendErrorMessage(100 + ((-1) * bufferCount));
return;
}
// Send the response message.
buffer[1] = 0x01;
bufferCount = 1 + (bufferCount * 2);
sendMessage(buffer + 1, bufferCount);
}
void handleMessage(uint8_t *buffer, int bufferCount)
{
if (bufferCount < 1) {
sendErrorMessage(ERROR_INVALID_MESSAGE);
return;
}
uint8_t command = buffer[0];
if (command == COMMAND_RESET) {
handleResetCommand(buffer + 1, bufferCount - 1);
} else if (command == COMMAND_TRANSMIT_RECEIVE) {
handleTransmitReceiveCommand(buffer + 1, bufferCount - 1);
} else {
sendErrorMessage(ERROR_UNKNOWN_COMMAND);
}
}
void handleFrame(uint8_t *buffer, int bufferCount)
{
if (bufferCount < 4) {
sendErrorMessage(ERROR_INVALID_MESSAGE);
return;
}
int count = (buffer[0] << 8) | buffer[1];
if (bufferCount - 4 != count) {
sendErrorMessage(ERROR_INVALID_MESSAGE);
return;
}
handleMessage(buffer + 2, count);
}
void setup()
{
// Configure serial port and state machine.
Serial.begin(115200);
frameState = WAIT_START;
while (Serial.available() > 0) {
Serial.read();
}
// Configure the transceiver.
CoaxTransceiver::setup();
}
void loop()
{
if (Serial.available() > 0) {
uint8_t byte = Serial.read();
if (frameState == WAIT_START) {
if (byte == FRAME_END) {
frameState = DATA;
}
} else if (frameState == DATA) {
if (byte == FRAME_END) {
if (frameBufferCount > 0) {
handleFrame(frameBuffer, frameBufferCount);
}
frameBufferCount = 0;
} else if (byte == FRAME_ESCAPE) {
frameState = ESCAPE;
} else {
// TODO: overflow...
frameBuffer[frameBufferCount++] = byte;
}
} else if (frameState == ESCAPE) {
if (byte == FRAME_ESCAPE_END) {
// TODO: overflow...
frameBuffer[frameBufferCount++] = FRAME_END;
} else if (byte == FRAME_ESCAPE_ESCAPE) {
// TODO: overflow...
frameBuffer[frameBufferCount++] = FRAME_ESCAPE;
}
frameState = DATA;
}
}
}