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Serial Com and LPT Header/Cables for B250M-A Motherboard?

Level 9
I recently picked up a used computer with a Prime B250M-A board in it. I would actually like to use the LPT and Serial ports available on the M/B. I do not think these come with the board in the first place. But I don't have them in any case.

Where can I get them and what do I have to look for specifically or avoid? For example, I have seen some discussions on some of the serial headers asking "connector dtk/intel or at/everex pinout?" No idea about this or if there is similar for LPT.

Any pointers are appreciated.


Level 14
You can find the pinouts for ASUS COM & LPT headers here:


That URL suggests it's for the Z170-K board, but it's linked from the PRIME B250M-A Manual page. I'd be surprised if ASUS have multiple different pinout for those headers, so it's likely standard across all their boards that have them.

From a quick search and cross-reference, it looks like the ASUS COM port is AT/Everex pinout. Serial ports should be robust as far as using the incorrect pins, as long as what they are connected to is another serial port, so it's fairly safe.

I'd guess the LPT header is probably standard. The DB-25 parallel port on the back of PCs certainly was very standard, the IBM/Centronics/IEEE1284 pinout, but I'm not certain about the PCB headers.