From ChatGPT:
Yes, adding the line [all] gpio=21=op,dh to your config.txt file does indeed suggest that pin 21 will go high during the boot process. However, this configuration applies when the operating system is booting, but it doesn't necessarily mean that the pin will go high before the bootloader phase.
The [all] section in config.txt is applied to all Raspberry Pi models and specifies that GPIO pin 21 should be set as an output (op) and driven high (dh) as soon as the configuration is loaded. This typically occurs during the bootloader's initialization process but after the initial bootloader stage, which is responsible for loading the firmware and reading config.txt.
So, while the pin will go high early in the boot process, it will happen after the first stage of the bootloader has initialized and read the configuration file. If you need the pin to go high even before the bootloader initializes, you would likely need to modify the bootloader itself, which is not commonly done.
If you need this pin to be high at the very earliest possible stage, such as right at the start of the boot process, you would need to look into hardware-level configurations or custom bootloader modifications.
Yes, adding the line [all] gpio=21=op,dh to your config.txt file does indeed suggest that pin 21 will go high during the boot process. However, this configuration applies when the operating system is booting, but it doesn't necessarily mean that the pin will go high before the bootloader phase.
The [all] section in config.txt is applied to all Raspberry Pi models and specifies that GPIO pin 21 should be set as an output (op) and driven high (dh) as soon as the configuration is loaded. This typically occurs during the bootloader's initialization process but after the initial bootloader stage, which is responsible for loading the firmware and reading config.txt.
So, while the pin will go high early in the boot process, it will happen after the first stage of the bootloader has initialized and read the configuration file. If you need the pin to go high even before the bootloader initializes, you would likely need to modify the bootloader itself, which is not commonly done.
If you need this pin to be high at the very earliest possible stage, such as right at the start of the boot process, you would need to look into hardware-level configurations or custom bootloader modifications.
Statistics: Posted by h_smith_usa — Mon Sep 02, 2024 6:16 pm