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geekhack Community => Keyboards => Topic started by: jkercado on Wed, 14 December 2011, 21:14:24

Title: Good news and bad news: NEC APC-H412
Post by: jkercado on Wed, 14 December 2011, 21:14:24
I had the good fortune to find a NEC APC-H412 in relatively decent condition for cheap. I tested a few keys randomly and it worked okay. After extensive cleanup I started to really test-drive it, typing stuff on Notepad. Unfortunately, it seems to be "missing" keystrokes at random. The switches click deliciously, but I have to say it skips around 15%-20% fo what I type. And it's all different keys.

Could it be the blue cube? Or if it's the keyboard itself, what should I look for in it? Where do I get started in troubleshooting?

Thanks!
Title: Good news and bad news: NEC APC-H412
Post by: alaricljs on Wed, 14 December 2011, 22:18:23
It's unlikely to be the board if it's not skipping all the same keys.  MCUs generally don't fail in that sort of way unless they are on the edge of their thermal envelope.
Title: Good news and bad news: NEC APC-H412
Post by: jkercado on Wed, 14 December 2011, 22:19:39
Did some more testing...Some of the keys are getting "stuck" even though the switch has returned. Only way to stop it is to hit the offending repeating key again. I'm mystified...
Title: Good news and bad news: NEC APC-H412
Post by: alaricljs on Wed, 14 December 2011, 22:22:40
Well, that is definitely MCU related, the question becomes is it the board or the cube?  Time to ask around friends/work for someone that has a PS/2 system perhaps.
Title: Good news and bad news: NEC APC-H412
Post by: jkercado on Wed, 14 December 2011, 22:26:06
Quote from: alaricljs;471040
Well, that is definitely MCU related, the question becomes is it the board or the cube?  Time to ask around friends/work for someone that has a PS/2 system perhaps.

I'll take it to the office tomorrow and see what happens, my work PC has a PS/2 port, plus my co-workers are not surprised at all to see me walking in with old humongous keyboards. :becky:
Title: Good news and bad news: NEC APC-H412
Post by: jkercado on Thu, 15 December 2011, 08:30:30
Good news! It seems to be that the NEC is not compatible with the Blue cube. Whew! Working perfectly connected to my work PC's PS/2 port. Nice keyboard!
Title: Re: Good news and bad news: NEC APC-H412
Post by: cyrax on Sat, 26 January 2013, 03:03:28
*BUMP*
I have the same NEC keyboard. Works fine with a desktop PS/2 socket. I was wondering if you had any luck finding a PS/2 to USB converter. The cube did not work for me either.
Title: Re: Good news and bad news: NEC APC-H412
Post by: cyrax on Sat, 26 January 2013, 04:06:39
As was noted in another thread, I am trying with a Belkin converter. Let's see how it goes.