nfg.forums

NFG Forums => SIG X68000 => Topic started by: e1000 on January 03, 2014, 11:10:06 AM

Title: Question about KGB-PRK II
Post by: e1000 on January 03, 2014, 11:10:06 AM
Folks, I got this memory expansion card. It is a "KGB-PRK II".

I didn't connected it yet to a X68...

However, considering this card has all memory modules in place (16 memory ICs), how much memory it would add to a X68?

http://www.flickr.com/photos/85569972@N00/11325799064/#in/set-72157638742278433 (http://www.flickr.com/photos/85569972@N00/11325799064/#in/set-72157638742278433)
Title: Re: Question about KGB-PRK II
Post by: Neshek on January 03, 2014, 11:29:36 AM
I'm not totally sure..
But..
With those jumpers on, i'll bet on 8mb :)

Congratulations :)
Title: Re: Question about KGB-PRK II
Post by: e1000 on January 03, 2014, 11:42:38 AM
Hi Neshek,

Thanks for your reply.

Indeed, I searched the internet for the memory IC datasheet (HM514400AZ8).

I found that this IC is a "1,048,576-WORD x 4-BIT DYNAMIC RAM".

http://www.alldatasheet.com/view.jsp?Searchword=HM514400AZ8 (http://www.alldatasheet.com/view.jsp?Searchword=HM514400AZ8)

Thus, if I'm not wrong, each memory IC holds 512KB, since there's 16 of them, you are right: the card has 8 MB.
Title: Re: Question about KGB-PRK II
Post by: Neshek on January 04, 2014, 12:52:00 AM
BTW, where did you get this 8mb board?

Was it expensive?
Title: Re: Question about KGB-PRK II
Post by: cr4zymanz0r on January 04, 2014, 08:35:27 AM
It is indeed a 8MB expansion card when fully populated.
I had one that only had half the memory chips in it which I then soldered in more bringing it from 4MB to 8MB. I had a post about it here http://nfggames.com/forum2/index.php?topic=5170.0 (http://nfggames.com/forum2/index.php?topic=5170.0). The jumper settings in your pic are correct for 8MB too.
Title: Re: Question about KGB-PRK II
Post by: e1000 on January 06, 2014, 07:50:46 AM
Hi Neshek,

I purchased this card from Shopping Mall Japan.

It was a bit expensive, which is unfortunately the standard for such X68 hardware.  :(

Best regards,

e1000