BIT Linux ARM CTS Stuck Low w/ DisableCTS Set

[PXCScott]

Running V5 (1027) ..

I have RTS / CTS / DSR / DTR disabled (I think)

Relevant Serial port section from cmdline_config.txt

## Device to test - ttys0, ttys1 etc to ttys63
Device ttymxc0
## Test Mode - Loopback or Detect
TestMode Loopback

## Disable RTS/CTS and DSR/DTR
DisableRTS
DisableCTS
DisableDSR
DisableDTR
## Send and receive timeout, 100-30000 ms
#SendReceive 3500
## Baud rate - 110, 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200,
## Cycle to 115200 (Cycle115), 230400, Cycle to 230400 (Cycle230), 460800,921600
BaudRate 115200
</Serial>

Log entries

******************
DETAILED EVENT LOG
******************
LOG NOTE: 2026-11-04 15:51:27, Disk: Hard Disk (/run/media/mmcblk2p2) [/dev/mmcblk2p2], Each file size is: 63 blocks of 16384 bytes (0 MB, 1032192 Bytes)
LOG NOTE: 2026-11-04 15:52:02, Serial Port: ttymxc0, /dev/ttymxc0: CTS stuck low
SERIOUS: 2026-11-04 15:52:02, Serial, COM port Clear To Send (CTS) line stuck low
LOG NOTE: 2026-11-04 15:52:38, Serial Port: ttymxc0, /dev/ttymxc0: CTS stuck low
SERIOUS: 2026-11-04 15:52:38, Serial, COM port Clear To Send (CTS) line stuck low
LOG NOTE: 2026-11-04 15:53:13, Serial Port: ttymxc0, /dev/ttymxc0: CTS stuck low
SERIOUS: 2026-11-04 15:53:13, Serial, COM port Clear To Send (CTS) line stuck low
LOG NOTE: 2026-11-04 15:53:49, Serial Port: ttymxc0, /dev/ttymxc0: CTS stuck low
SERIOUS: 2026-11-04 15:53:49, Serial, COM port Clear To Send (CTS) line stuck low
LOG NOTE: 2026-11-04 15:54:25, Serial Port: ttymxc0, /dev/ttymxc0: CTS stuck low
SERIOUS: 2026-11-04 15:54:25, Serial, COM port Clear To Send (CTS) line stuck low
LOG NOTE: 2026-11-04 15:55:01, Serial Port: ttymxc0, /dev/ttymxc0: CTS stuck low
SERIOUS: 2026-11-04 15:55:01, Serial, COM port Clear To Send (CTS) line stuck low
LOG NOTE: 2026-11-04 15:55:36, Serial Port: ttymxc0, /dev/ttymxc0: CTS stuck low
SERIOUS: 2026-11-04 15:55:36, Serial, COM port Clear To Send (CTS) line stuck low
LOG NOTE: 2026-11-04 15:56:12, Serial Port: ttymxc0, /dev/ttymxc0: CTS stuck low
SERIOUS: 2026-11-04 15:56:12, Serial, COM port Clear To Send (CTS) line stuck low
LOG NOTE: 2026-11-04 15:56:48, Serial Port: ttymxc0, /dev/ttymxc0: CTS stuck low
SERIOUS: 2026-11-04 15:56:48, Serial, COM port Clear To Send (CTS) line stuck low
LOG NOTE: 2026-11-04 15:57:23, Serial Port: ttymxc0, /dev/ttymxc0: CTS stuck low
SERIOUS: 2026-11-04 15:57:23, Serial, COM port Clear To Send (CTS) line stuck low
LOG NOTE: 2026-11-04 15:57:55, Status, Test run stopped

Why is it trying CTS when I have DisableCTS.

NXP i.MX8MP with Yocto and Linux 6.12.3-lts-next-g37c02b8bfb4

[Simon (PassMark)]

Note that 'DisableRTS' will disable RTS+CTS and 'DisableDSR' will disable DSR+DTR
Might just be missing your excerpt, but each device should be in its own <Test> tags as well

## Serial Port - Have a <Test> section for each device to test
<Serial>

<Test>
## Device to test - ttyS0, ttyS1 etc to ttyS63
Device ttyS0
## Test Mode - Loopback or Detect
TestMode Loopback
</Test>


## Disable RTS/CTS flow control testing
DisableRTS
## Disable DSR/DTR flow control testing
DisableDSR
## Send and receive timeout, 100-30000 ms
SendReceive 3500
## Baud rate - 110, 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200,
##            Cycle to 115200 (Cycle115), 230400, Cycle to 230400 (Cycle230), 460800,921600
BaudRate 115200
</Serial>

If it still does not work, can you run in debug mode (with '-d' parameter), reproduce issue, and send the generated debug.log file as well as your entire cmdline_config.txt