Improves power usageHEADmaster

1 files changed, 40 insertions, 8 deletions

diff --git a/README.md b/README.md
index 8d22b40..c2c0385 100644
--- a/README.md
+++ b/README.md
@@ -5,26 +5,58 @@ Experimental control software for robotics, tested on Raspberry Pi 5.
 To configure the system, the files in the `sysconf` directory must be
 installed:
 
-1. Copy the UDEV `*.rule` files into `/etc/udev/rules.d`.
-2. Copy `config.txt` to `/boot`.
-3. Reboot the Raspberry Pi for the changes to take effect.
+1. Copy the UDEV `*.rule` files into `/etc/udev/rules.d`
+2. Copy `config.txt` to `/boot`
+3. Reboot the Raspberry Pi for the changes to take effect
+
+## Low Power Consumption When Powered Off:
+By default, the Raspberry Pi 5 keeps the SoC powered on (in a shutdown state)
+even after the system is shut down. As a result, it continues to consume
+1.2-1.6W of power, even with nothing plugged in except for power. For more
+details, see:
+[Reducing Raspberry Pi 5's Power Consumption](https://www.jeffgeerling.com/blog/2023/reducing-raspberry-pi-5s-power-consumption-140x)
+
+This can be easily fixed by editing the EEPROM configuration with the
+following command:
+```console
+user@alarm$ sudo rpi-eeprom-config -e
+```
+Ensure that `POWER_OFF_ON_HALT=1` is set, while leaving the other variables
+unchanged:
+```config
+[all]
+BOOT_UART=[...]
+POWER_OFF_ON_HALT=1
+BOOT_ORDER=[...]
+```
+
+To run `rpi-eeprom-config` on Arch Linux, you’ll need to install the
+`rpi5-eeprom` package from the `PKGBUILDs` repository. Run the following
+commands to do so:
+```console
+user@alarm$ git clone https://github.com/archlinuxarm/PKGBUILDs
+user@alarm$ cd PKGBUILDs/alarm/rpi-eeprom
+user@alarm$ makepkg -s
+user@alarm$ sudo pacman -U rpi5-eeprom-*.pkg.tar.xz
+```
 
 ## GPIO and PWM Access Without Root:
 To enable GPIO and PWM access without root privileges on the Raspberry Pi 5,
 follow these steps:
 
-1. Create two new user groups: `gpiod` and `pwm`.
-2. Add your user to both groups.
+1. Create two new user groups: `gpiod` and `pwm`
+2. Add your user to both groups
 3. The UDEV rules installed previously will grant the `gpiod` and `pwm` user
-groups permission to access the respective subsystems.
+   groups permission to access the respective subsystems.
 
 This configuration ensures that GPIO and PWM operations can be performed
 without needing root access.
 
 ## Build Instructions:
 1. Install [`stack`](https://docs.haskellstack.org/en/stable/). It’s
-recommended to use [`ghcup`](https://www.haskell.org/ghcup/) for installation.
-2. Run `stack build` to compile the libraries and executables.
+   recommended to use [`ghcup`](https://www.haskell.org/ghcup/) for
+   installation.
+2. Run `stack build` to compile the libraries and executables
 
 > Note: You may need to install system dependencies on your host first (e.g.,
 > `libgpiod`, etc.)