Hello,
I used the Fx30S to perform serial communication through Rs485. I give you here somme comments and questions.
The thread “http://forum.legato.io/t/fx30s-rs485-port-cannot-set-termination-resistor-gpio-63/2600” from the Legato forum gave me some good information.
Description of my environment:
- I am using a firmware built from the Yocto Legato-Dist-Source-mdm9x15-SWI9X15Y_07.11.21.00
- I have not modified any driver related to the serial links
The manipulation:
- I have configured the UART1 for the customer Linux application (AT!MAPUART=17), then rebooted the device
- I have been using a program (written in C) to access the UART.
Here are my remarks / questions:
- As said in the Legato forum, I confirm that the RS485 signal is on pins 1 and 2, and not on pins 1 and 3 as described in the user guide (rev 1).
- I do not have the entry “/sys/devices/platform/msm_serial_hsl.0/rs_term”, nor “…/rs485_term” existing on my system. Why is that?
- Is you driver totally compliant with TIOCSRS485? The call to “ioctl(ctx->s, TIOCSRS485, &rs485conf)” with “rs485conf.flags = SER_RS485_ENABLED” returns an error. I had to replace it with a write on “/sys/devices/platform/msm_serial_hsl.0/rs_mode”.
Best regards, Christian.