F5F Stay Refreshed Hardware Desktop UART Header for AsRock B650E PG-ITX

UART Header for AsRock B650E PG-ITX

UART Header for AsRock B650E PG-ITX

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mikewiebe
Junior Member
1
11-11-2017, 10:16 PM
#1
Hey there, I'm just the new owner of an AsRock B650E PG-ITX board. I came across a forum thread about six months ago that mentioned another AsRock model with a UART header. I’m curious if anyone else has used this port and knows its purpose. It doesn’t appear in Windows 10 or Linux device managers or chipset diagrams, and it’s not listed in the manual either. My guess is it’s meant to communicate with the firmware on the board—probably only factory-set. I’m also wondering if this relates to BIOS repair; I saw a discussion about fixing corrupted BIOS files via UART, but it sounds risky since UART lacks timing stability. I’m not sure if flashing the ROM over UART is realistic, given clock and signal issues. I’m thinking maybe using a Pi to test for data through it, but I don’t want to damage this $260 board. What does this header actually transmit?
M
mikewiebe
11-11-2017, 10:16 PM #1

Hey there, I'm just the new owner of an AsRock B650E PG-ITX board. I came across a forum thread about six months ago that mentioned another AsRock model with a UART header. I’m curious if anyone else has used this port and knows its purpose. It doesn’t appear in Windows 10 or Linux device managers or chipset diagrams, and it’s not listed in the manual either. My guess is it’s meant to communicate with the firmware on the board—probably only factory-set. I’m also wondering if this relates to BIOS repair; I saw a discussion about fixing corrupted BIOS files via UART, but it sounds risky since UART lacks timing stability. I’m not sure if flashing the ROM over UART is realistic, given clock and signal issues. I’m thinking maybe using a Pi to test for data through it, but I don’t want to damage this $260 board. What does this header actually transmit?

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IPS10
Senior Member
623
11-11-2017, 10:16 PM
#2
Checked other Asrock motherboard manuals for UART1 details. It seems related to digital audio output, though the optical connector is already present, which makes sense. The pinout of the cable with digital connectors matches what you'd expect, so it’s likely a digital audio header. You might want to use a multimeter to test for voltage on that header.
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IPS10
11-11-2017, 10:16 PM #2

Checked other Asrock motherboard manuals for UART1 details. It seems related to digital audio output, though the optical connector is already present, which makes sense. The pinout of the cable with digital connectors matches what you'd expect, so it’s likely a digital audio header. You might want to use a multimeter to test for voltage on that header.

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khyle5
Junior Member
14
11-11-2017, 10:16 PM
#3
It seems like you're questioning whether the setup is optical audio or not. You mention you could probably test it yourself but prefer not to physically connect everything. You also have a Raspberry Pi debug probe ready for UART communication if needed.
K
khyle5
11-11-2017, 10:16 PM #3

It seems like you're questioning whether the setup is optical audio or not. You mention you could probably test it yourself but prefer not to physically connect everything. You also have a Raspberry Pi debug probe ready for UART communication if needed.