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633 RS-232 to 2x5 Serial Connection Cable


New member
Is there any update on a direct way to connect from a standard 2x5.1" Internal Serial (Com2) to the RS-232 Connection on the 633? On my mini-ITX EPIA system I dont have much room for a combination of RS-232-to-DB9 cable with and additional Serial header-to-DB9 Male. I'd love a cable that was pre-made and a short length.
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New member
The problem is that there is no standard pin-out config for mobo. When swapping out old AT mobos I make sure I bring the serial cables along for the ride otherwise there is a good chance they won't work. They are always 2x5 just not always wired the same. You would have to do a detail check of the pin outs in the mobo manual and compare them to Crystalfontz's requirement. You could get lucky or at worst, have to wire your own.

CF Tech

Skip is right, there is no standard for the motherboard 2x5 serial headers. We have found there are two popular configurations however, and the 633 will support either of those configurations with jumper settings.

Basically start with a straight-through ribbon cable (go to http://www.digi-key.com and search for C3AAG-1018M for an example). If that does not work, use a soldering iron and some solder wick to carefully open jumpers J2, J4, and J6 on your 633, then close jumpers J1, J3 & J5 (see the RS-232 connections section of the manual for details). One of those two settings should work.

If you do not have experience working with fine electronics soldering, please find some who does have experience to help with closing and opening the jumpers.
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New member
Thanks. To be sure this is what I am trying to connect. I can leave the 633 jumpers alone, and use the default setting. But make a cable that connects teh following;

Epia M1000 - Serial Com2 Port Definitions
Pin Signal Description
1 DCD Data Carry Detect
2 SIN Serial In or Receive Data
3 SOUT Serial Out or Transmit Data
4 DTR Data Terminal Ready
5 GND Ground
6 DSR Data Set Ready
7 RTS Request To Send
8 CTS Clear to Send
9 RI Ring Indicate
10 N/A N/A

Crystal Fontz 633 - RS-232 Serial Connection Details (Default Setting)
3 LCD TX/Host RX Serial Transmit
5 LCD RX/Host TX Serial Receive
9 GND Ground

Basic Cable Needed Would Be
From PC/MoBo (2x5) To LCD (2x5)
Pin From (MoBo) Pin To (LCD)
2 <-- 3
3 --> 5
9 <--> 9

Are there other pins that I would need to connect? If so what to what?