EPICS Re: Reg : How to use custom baud rate such as 125000 for ioc running on Linux

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Hi Abhishek,

Maybe you can run this script as root/sudo to check the supported baud rates in your linux system:

for bauds in $(
    sed -r 's/^#define\s+B([1-9][0-9]+)\s+.*/\1/p;d' \
        /usr/include/asm-generic/termbits*.h ) ;do
    echo $bauds
    stty -F /dev/ttyS0 $bauds && echo Ok.
done  2>&1 |
    pr -at2

The output of the script on RHEL-8 system, I am running in one of my computer looks like this:

50				    Ok.
75				    Ok.
110				    Ok.
134				    Ok.
150				    Ok.
200				    Ok.
300				    Ok.
600				    Ok.
1200				    Ok.
1800				    Ok.
2400				    Ok.
4800				    Ok.
9600				    Ok.
19200				    Ok.
38400				    Ok.
57600				    Ok.
115200				    Ok.
230400				    Ok.
460800				    Ok.
500000				    Ok.
576000				    Ok.
921600				    Ok.
1000000				    Ok.
1152000				    Ok.
1500000				    Ok.
2000000				    stty: /dev/ttyS0: unable to perform
2500000				    stty: /dev/ttyS0: unable to perform
3000000				    stty: /dev/ttyS0: unable to perform
3500000				    stty: /dev/ttyS0: unable to perform
4000000				    stty: /dev/ttyS0: unable to perform

Best,

Mrinal

On Feb 28, 2024, at 4:42 AM, Abhishek Mazumdar - STFC UKRI via Tech-talk <tech-talk at aps.anl.gov> wrote:

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Hello,

I am running an ioc for a device in linux which supports 125000 baud rate using UART communication.

The vendor of the device has provided python libraries through which I am able to communicate with the device without any issues.

The vendor's python libraries uses python serial package to communicate with the port /dev/ttyUSB1 (for example) using baud rate 125000.

But when I am using the baud rate 125000 in my ioc's st.cmd , I am not able to communicate with the device.

How to communicate with the device using 125000 baudrate using EPICs IOC ?

Thanks,

Abhishek Mazumdar

Subject:	Re: Reg : How to use custom baud rate such as 125000 for ioc running on Linux
From:	Mrinal Bera via Tech-talk <tech-talk at aps.anl.gov>
To:	Abhishek Mazumdar - STFC UKRI <abhishek.mazumdar at stfc.ac.uk>
Cc:	"tech-talk at aps.anl.gov" <tech-talk at aps.anl.gov>
Date:	Wed, 28 Feb 2024 19:35:09 +0000

Experimental Physics and Industrial Control System