I’ve read one user on this forum being able to activate uarts (UARTA, UARTB, UARTC) on the 40 pins header.
It’s no problem for us to recompile the android image, but could you please give details on the pins number for each possible UART (if 4 UART are possible, please tell) ? And what modifications exactly are required before recompiling ?
Hello and welcome,
I believe you were referring to @davemf as he was able to add the extra UART, I am sure he will be able to help you modify it, but regarding a 4th UART, I am not sure if the hardware can support that, and even if it could it might not be in the GPIO…, @Terry might also be able to help you…
Hi @davemf I’ve installed latest ubuntu desktop from here but no ttyS3 is inside on my /dev folder. I’ve also try to use approach found in this how to without success.
Any suggestions about ? I’m not able to communicate with uart using ttyS0 or ttyS1.
And in console I see (I’ve disable Linux cosole for UART0):
khadas@Khadas:~$ ls -ltrh /dev/ttyS*
crw-rw---- 1 root dialout 236, 0 Mar 23 13:45 /dev/ttyS0
crw-rw---- 1 root dialout 236, 1 Mar 23 13:45 /dev/ttyS1
And here there is no ttyS3.
And when I access ttyS1, I also can’t send any data.
On PC side I have other application.
But I don’t see the signals even with logic analyzer.
With Linux_RX/TX I see. It’s working well.
With UARTC it’s not.
I’m sure.
I have two available ports:
crw-rw---- 1 root dialout 236, 0 Mar 23 13:45 /dev/ttyS0
crw-rw---- 1 root dialout 236, 1 Mar 23 13:45 /dev/ttyS1
S0 is working correct, S1 is not working. And I have no S3.