gmmoreira · March 6, 2025 14:40 · Mar 6, 2025 · Feb 16, 2023 · Apr 8, 2022
diff --git a/commands.sh b/commands.sh
@@ -32,12 +32,17 @@ avrdude -c avr109 -p m32u4 -P /dev/ttyACM0 -n
 # -P /dev/ttyACM0 set the serial port. On Windows it would be something like COM1, COM7, etc...
 # -n disables any writes, it's safe option
 
-# Arduino as ISP
-# Flasing using Arduino as ISP
+# I don't know if my clone Pro Micro had a issue of I bricked it somehow, but I couldn't write to it by just using the reset to bootloader
+# So another solution was flashing it using a ISP programmer. I have a Uno R3 and after some research I discovered that I could use it as ISP.
+
+# Arduino UNO R3 as ISP
+# You can find more details about wiring and flashing the ISP here: https://docs.arduino.cc/built-in-examples/arduino-isp/ArduinoISP/#use-arduino-as-isp
+# To flash the Pro Micro through the Uno R3 ISP, use this command. caterina.hex is the binary you want to flash.
 avrdude -v -p m32u4 -P /dev/ttyUSB0 -c stk500v1 -b 19200 -U flash:w:caterina.hex:i -U lfuse:w:0xff:m -U hfuse:w:0xd8:m -U efuse:w:0xfb:m
 
-# Arduino has an autoreset feature which resets the device when a serial connection is opened, so avrdude will fail because Arduino will be reseting and not ready. 
+# Arduino UNO R3 has an autoreset feature which resets the device when a serial connection is opened, so avrdude will fail because Arduino will be reseting and not ready. 
 # To prevent this, one option to use a capacitor in some pins (google it, dont remember) or cut some traces on the board.
 # In Linux there's a simple option. It's possible to use the following command
 stty -F /dev/ttyUSB0 -hupcl
-# It will prevent the autoreset by not sending the hangup (something like that, I dont understand much about serial connections).
+# It will prevent the autoreset by not sending the hangup (something like that, I dont understand much about serial connections).
+# After this command you can use the avrdude command above.
diff --git a/commands.sh b/commands.sh
@@ -30,4 +30,14 @@ avrdude -c avr109 -p m32u4 -P /dev/ttyACM0 -n
 # -c avr109 set the programer as avr109. It's the protocol which will be used
 # -p m32u4 set the target, which is an atmega32u4
 # -P /dev/ttyACM0 set the serial port. On Windows it would be something like COM1, COM7, etc...
-# -n disables any writes, it's safe option
+# -n disables any writes, it's safe option
+
+# Arduino as ISP
+# Flasing using Arduino as ISP
+avrdude -v -p m32u4 -P /dev/ttyUSB0 -c stk500v1 -b 19200 -U flash:w:caterina.hex:i -U lfuse:w:0xff:m -U hfuse:w:0xd8:m -U efuse:w:0xfb:m
+
+# Arduino has an autoreset feature which resets the device when a serial connection is opened, so avrdude will fail because Arduino will be reseting and not ready. 
+# To prevent this, one option to use a capacitor in some pins (google it, dont remember) or cut some traces on the board.
+# In Linux there's a simple option. It's possible to use the following command
+stty -F /dev/ttyUSB0 -hupcl
+# It will prevent the autoreset by not sending the hangup (something like that, I dont understand much about serial connections).
diff --git a/commands.sh b/commands.sh
@@ -0,0 +1,33 @@
+# Using bootloader
+# To enter bootloader, connect the board to the computer and connect briefly the GND and RST pins. 
+# Some boards may require this connection to be done twice.
+# When the bootloader is running, a virtual serial connection is created and so we can read/write to the device
+
+# Checking connection and fuses
+avrdude -c avr109 -p m32u4 -P /dev/ttyACM0 -n
+
+# It should write something like the example below
+# Connecting to programmer: .
+# Found programmer: Id = "CATERIN"; type = S
+#    Software Version = 1.0; No Hardware Version given.
+# Programmer supports auto addr increment.
+# Programmer supports buffered memory access with buffersize=128 bytes.
+
+# Programmer supports the following devices:
+#    Device code: 0x44
+
+# avrdude: AVR device initialized and ready to accept instructions
+
+# Reading | ################################################## | 100% 0.00s
+
+# avrdude: Device signature = 0x1e9587 (probably m32u4)
+
+# avrdude: safemode: Fuses OK (E:FB, H:D8, L:FF)
+
+# avrdude done.  Thank you.
+
+# Explaining the command:
+# -c avr109 set the programer as avr109. It's the protocol which will be used
+# -p m32u4 set the target, which is an atmega32u4
+# -P /dev/ttyACM0 set the serial port. On Windows it would be something like COM1, COM7, etc...
+# -n disables any writes, it's safe option