Composite over GPIO: I just tested it on a Raspberry Pi 5 and it does work. It should work on CM5 too.
First, you need to make the driver change I mentioned above, to set the VIDEO_OUT_CFG_SEL_PAD_MUX flag in rp1_vec_cfg.c.
Then enable composite output, e.g. with:and configure the GPIO pins for DPI using Device Tree; or for a quick test, remotely log in and type:My rough-and-ready test circuit, which will win no prizes for image quality or EMC, was:
First, you need to make the driver change I mentioned above, to set the VIDEO_OUT_CFG_SEL_PAD_MUX flag in rp1_vec_cfg.c.
Then enable composite output, e.g. with:
Code:
dtoverlay=vc4-kms-v3d,compositeCode:
pinctrl set 4-11 a1Code:
GPIO11 ----[ 330R ]----+ |GPIO10 ----[ 680R ]----+ +------> VideoGPIO9 ----[ 1.2K ]----+ | (75R load)GPIO8 ----[ 2.2K ]----+GND --------------------------> GNDStatistics: Posted by njh — Thu Jul 24, 2025 3:00 pm