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From: schellew@wu2.wl.aecl.ca (Wayne Schellekens)
Subject: WANTED: DRAM Controller for use with MC68HC16
Message-ID: <1993Apr5.205055.27475@cu23.crl.aecl.ca>
Keywords: DRAM, HC16
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Organization: AECL Research, Whiteshell Laboratories
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Date: Mon, 5 Apr 1993 20:50:55 GMT
For an upcoming project I want to use 4 Megs of DRAM configured as two 2
Meg banks of 16 bit data. I was wondering if anyone out there knows of a
DRAM controller which will handle refreshing the data. It's ok if the
controller doesn't handle bank switching - that part is easy.
The only controllers I know of are the ones out of the National
Semiconductor DRAM Management Handbook (1988 edition) eg. DP8429. I would
like to know if another manufacturer produces one which may be easier to
implement in my circuit.
BTW, if anyone is wanting to hook up DRAM to a microcontroller, Dallas
Semiconductor makes a neat chip: the DS1262 Serial DRAM Nonvolatizer
Chip. It uses the SPI (I2C) bus and refreshes/controls up to 16Mx1 of DRAM
memory. It can use an external battery to refresh the DRAM when the
power is off. Price is $11.75 from Dallas (quan 1). I wish I could use
this chip but its maximum SPI clock rate is 1 MHz (too slow for me...).
Thanks in advance,
Wayne Schellekens
--
Wayne Schellekens, VE4WTS Internet: schellew@wu2.wl.aecl.ca
AECL Research AX.25: VE4WTS@VE4KV.#WPG.MB.CAN
Whiteshell Laboratories Twisted pair: (204)753-2311 x2317
dift1010@iro.umontreal.ca