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Re: RAM Errors with 16K card

Subject: Re: RAM Errors with 16K card
From: Patrick Schaefer <PSchaefer@epost.de>
Date: Sat, 20 Nov 2004 15:40:17 +0100
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Antony Mauget wrote:

Curiously, there is a variable resistor (don't know the english word) at the
top of the card.

This is to adjust the refresh timing for the dynamic RAM chips. Oldercards hat a cable that was connected to a RAM socket on the main pcb forthat purpose, here the refresh timing was derived from the main RAM.

This card will not work in a IIe because its 16k (from $D000-FFFF) wouldbe connected in parallel with the on-board RAM. It is intended to expanda 48k Appl ][ to the IIe's 64k.



Patrick

References:
- RAM Errors with 16K card
  - From: "Antony Mauget" <amauget@hotmail.com>
- Re: RAM Errors with 16K card
  - From: mjmahon@aol.com (Michael J. Mahon)
- Re: RAM Errors with 16K card
  - From: "Antony Mauget" <amauget@hotmail.com>

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