Displays with 4.3" and 16:9 ratio like the one below are available from Chinese outlets for less than $10. Resolution is 480x272 but it's not clear if that's the raw resolution or actual RGB pixels. Power supply is 12-24V (actually 9-34V). Two video inputs are provided, one has priority. If used with a rear-view camera the lower-priority input can be used as a status display. If no video input is provided the display is in standby.
My monitor has a native resolution of 272 lines. I'm not sure to which TV standard that corresponds (maybe PAL?) but with the help of an SSH session the command tvservice -c "NTSC 4:3 P"
results in a stable image. I'd like switch to TV-out mode; for this purpose the command shows the corresponing sdtv_mode
value for /boot/config.txt
. I had to adjust the overscan
settings to use the full