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@Manawyrm
Created Apr 12, 2022
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Hacky script to use an ESP32 as an emergency BIOS/UEFI recovery flasher
// WARNING!
// THIS SCRIPT IMMEDIATELY ERASES ANY CONNECTED SPI FLASH ROMS AFTER STARTUP!
// WARNING!
// Wiring:
// ESP32 CS0 (GPIO 5) - Flash /CS (Pin 1)
// ESP32 MISO (GPIO 19) - Flash DO (Pin 2)
// ESP32 GPIO 2 - Flash /WP (Pin 3)
// ESP32 GND - Flash GND (Pin 4)
// ESP32 MOSI (GPIO 23) - Flash DI (Pin 5)
// ESP32 V_SPI_CLK (GPIO 35) - Flash CLK (Pin 6)
// ESP32 V_SPI_HD (GPIO 21) - Flash /HOLD (Pin 7)
// ESP32 3V3 - Flash VCC (Pin 8)
#include <Arduino.h>
#include <SPIMemory.h>
int8_t SPIPins[4] = {-1, -1, -1, 33};
SPIFlash flash;
bool getID() {
uint32_t JEDEC = flash.getJEDECID();
if (!JEDEC) {
Serial.println("No comms. Check wiring. Is chip supported? If unable to fix, raise an issue on Github");
return false;
}
else {
Serial.print("JEDEC ID: 0x");
Serial.println(JEDEC, HEX);
Serial.print("Man ID: 0x");
Serial.println(uint8_t(JEDEC >> 16), HEX);
Serial.print("Memory ID: 0x");
Serial.println(uint8_t(JEDEC >> 8), HEX);
Serial.print("Capacity: ");
Serial.println(flash.getCapacity());
Serial.print("Max Pages: ");
Serial.println(flash.getMaxPage());
}
return true;
}
uint8_t buffer[4099];
void setup() {
Serial.begin(115200);
while (!Serial) ; // Wait for Serial monitor to open
delay(50); //Time to terminal get connected
Serial.print(F("Initialising"));
for (uint8_t i = 0; i < 10; ++i)
{
Serial.print(F("."));
}
Serial.println();
if (flash.error()) {
Serial.println(flash.error(VERBOSE));
}
// H_SPI_WP (write protect) pin
pinMode(2, OUTPUT);
digitalWrite(2, HIGH);
// V_SPI_HD (hold) pin
pinMode(21, OUTPUT);
digitalWrite(21, HIGH);
flash.begin();
getID();
flash.eraseChip();
Serial.println("E");
uint32_t address = 0;
// 8 MiB, change this to your flash size
while (address < (8 * 1024 * 1024))
{
Serial.println("W");
for (uint32_t i = 0; i < 4096; i++)
{
while (!Serial.available());
buffer[i] = Serial.read();
}
flash.writeByteArray(address, buffer, 4096);
address += 4096;
}
}
void loop() {
Serial.println("done!");
delay(1000);
}
@maj113
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maj113 commented Apr 24, 2022

looks promising, might test it out

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