130 lines
No EOL
5 KiB
C++
130 lines
No EOL
5 KiB
C++
/*
|
|
* This file is part of the "bluetoothheater" distribution
|
|
* (https://gitlab.com/mrjones.id.au/bluetoothheater)
|
|
*
|
|
* Copyright (C) 2018 Ray Jones <ray@mrjones.id.au>
|
|
*
|
|
* This program is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <https://www.gnu.org/licenses/>.
|
|
*
|
|
*/
|
|
|
|
//
|
|
// We need to identify the PCB the firmware is running upon for 2 reasons related to GPIO functions
|
|
//
|
|
// 1: Digital Inputs
|
|
// To the outside world, the digital inputs are always treated as contact closures to ground.
|
|
// V1.0 PCBs expose the bare ESP inputs for GPIO, they are normally pulled HIGH.
|
|
// V2.0+ PCBs use an input conditioning transistor that inverts the sense state.
|
|
// Inactive state for V1.0 is HIGH
|
|
// Inactive state for V2.0+ is LOW
|
|
//
|
|
// 2: Analogue input
|
|
// Unfortunately the pin originally chosen for the analogue input on the V2.0 PCB goes to
|
|
// an ADC2 channel of the ESP32.
|
|
// It turns out NONE of the 10 ADC2 channels can be used if Wifi is enabled!
|
|
// The remedy on V2.0 PCBs is to cut the traces leading from Digital input 1 and the Analogue input.
|
|
// The signals are then tranposed.
|
|
// This then presents Digital Input #1 to GPIO26, and analogue to GPIO33.
|
|
// As GPIO33 uses an ADC1 channel no issue is present reading analogue values with wifi enabled.
|
|
//
|
|
// Board Detection
|
|
// Fortunately due to the use of the digital input transistors on V2.0+ PCBs, a logical
|
|
// determination of the board configuration can be made.
|
|
// By setting the pins as digital inputs with pull ups enabled, the logic level presented
|
|
// can be read and thus the input signal paths can be determined.
|
|
// Due to the input conditioning transistors, V2.0 PCBs will hold the inputs to the ESP32
|
|
// LOW when inactive, V1.0 PCBs will pull HIGH.
|
|
// Likewise, the analogue input is left to float, so it will always be pulled HIGH.
|
|
// NOTE: a 100nF capacitor exists on the analogue input so a delay is required to ensure
|
|
// a reliable read.
|
|
//
|
|
// Input state truth table
|
|
// GPIO26 GPIO33
|
|
// ------ ------
|
|
// V1.0 HIGH HIGH
|
|
// unmodified V2.0 HIGH LOW
|
|
// modified V2.0 LOW HIGH
|
|
// V2.1 LOW HIGH
|
|
//
|
|
//
|
|
// ****************************************************************************************
|
|
// This test only needs to be performed upon the very first firmware execution.
|
|
// Once the board has been identified, the result is saved to non volatile memory
|
|
// If a valid value is detected, the test is bypassed.
|
|
// This avoids future issues should the GPIO inputs be legitimately connected to
|
|
// extension hardware that may distort the test results when the system is repowered.
|
|
// ****************************************************************************************
|
|
//
|
|
|
|
#include "BoardDetect.h"
|
|
#include <Preferences.h>
|
|
#include <driver/adc.h>
|
|
#include "DebugPort.h"
|
|
|
|
void BoardRevisionReset()
|
|
{
|
|
Preferences preferences;
|
|
|
|
preferences.begin("System Info", false);
|
|
preferences.clear();
|
|
}
|
|
|
|
int BoardDetect()
|
|
{
|
|
Preferences preferences;
|
|
|
|
preferences.begin("System Info", false);
|
|
|
|
uint8_t revision = 0;
|
|
uint8_t val = preferences.getUChar("Board Revision", revision);
|
|
if(val != 0) {
|
|
DebugPort.printf("Board detect: Using saved revision V%.1f\r\n", float(val) * 0.1f);
|
|
return val;
|
|
}
|
|
|
|
DebugPort.println("Board detect: Virgin system - attempting to detect revision");
|
|
pinMode(33, INPUT_PULLUP);
|
|
pinMode(26, INPUT_PULLUP);
|
|
// there is a 100nF capacitor across the analogue input, allow that to charge before testing
|
|
delay(100);
|
|
int pin33 = digitalRead(33);
|
|
int pin26 = digitalRead(26);
|
|
|
|
if(pin33 == HIGH && pin26 == HIGH) {
|
|
revision = 10;
|
|
DebugPort.println("Board detect: digital input test reveals V1.x PCB");
|
|
}
|
|
else if(pin33 == LOW && pin26 == HIGH) {
|
|
revision = 20;
|
|
DebugPort.println("Board detect: digital input test reveals V2.0 PCB");
|
|
}
|
|
else if(pin33 == HIGH && pin26 == LOW) {
|
|
revision = 21;
|
|
DebugPort.println("Board detect: digital input test reveals V2.1 PCB");
|
|
}
|
|
else {
|
|
DebugPort.println("Board detect: digital input test failed to detect a valid combination!!!");
|
|
}
|
|
|
|
pinMode(33, INPUT); // revert to normal inputs (remove pull ups)
|
|
pinMode(26, INPUT);
|
|
|
|
//store the detected revision
|
|
if(revision) {
|
|
preferences.putUChar("Board Revision", revision);
|
|
}
|
|
|
|
DebugPort.printf("Board detect: Result = V%.1f\r\n", float(revision)*0.1f);
|
|
return revision;
|
|
} |