Difference between revisions of "DRAMS"

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(pinouts and minimal description of DRAM chips used in ZX Spectrum 16/48)
 
(4532)
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The A<sub>7</sub> line is omitted for refresh address.
 
The A<sub>7</sub> line is omitted for refresh address.
 +
 +
===4164===
 +
64Kx1 bit DRAM chip
 +
 +
16 of this IC make the 128K RAM of the ZX Spectrum48 RAM.
 +
 +
e.g:NEC D4164C-3
 +
 +
Pinout:
 +
 +
<tt>
 +
{|
 +
| style="text-align:right;" |
 +
NC<br>
 +
D<sub>IN</sub><br>
 +
{{overline|WE}}<br>
 +
{{overline|RAS}}<br>
 +
A<sub>0</sub><br>
 +
A<sub>2</sub><br>
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A<sub>1</sub><br>
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(+5V) V<sub>CC</sub>
 +
| style="border: 1px solid black" |
 +
1&nbsp;°&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;16<br>
 +
2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;15<br>
 +
3&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;14<br>
 +
4&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;13<br>
 +
5&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;12<br>
 +
6&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;11<br>
 +
7&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;10<br>
 +
8&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;9
 +
||
 +
GND (0V)<br>
 +
{{overline|CAS}}<br>
 +
D<sub>OUT</sub><br>
 +
A<sub>6</sub><br>
 +
A<sub>3</sub><br>
 +
A<sub>4</sub><br>
 +
A<sub>5</sub><br>
 +
A<sub>7</sub><br>
 +
|}
 +
</tt>

Revision as of 18:03, 17 October 2016

DRAMS

Dynamic Random Access Memories used in ZX Sopectrum machines.

4116

16Kx1 bit DRAM chip

8 of this IC make the lower 16k part of the ZX Spectrum16/48 RAM.

e.g. NEC D416C-2

Pinout:

(-5V) VEE
DIN
WE
RAS
A0
A2
A1
(+12V) VDD

1 °     16
2       15
3       14
4       13
5       12
6       11
7       10
8        9

GND (0V)
CAS
DOUT
A6
A3
A4
A5
VCC (+5V)

4532

32Kx1 bit DRAM chip

The addressing logic uses 8 line (A0 to A7) for row address (RAS) and 7 line (A0 to A6) for column address (CAS). At CAS the A7 line has to be fixed at logic 0 or 1 depending on chip type.

8 of this IC make the upper 32k part of the ZX Spectrum48 RAM.

e.g: TI TMS4532-20NL3 or OKI M3732-L TI TMS4532-20NL4 or OKI M3732-H

Pinout:

NC
DIN
WE
RAS
A0
A2
A1
(+5V) VCC

1 °     16
2       15
3       14
4       13
5       12
6       11
7       10
8        9

GND (0V)
CAS
DOUT
A6
A3
A4
A5
A7

A7 should set logical 0 at CAS for TI TMS4532-20NL3 and OKI M3732-L chips, and logical 1 for TI TMS4532-20NL4 and OKI M3732-H chips.

The A7 line is omitted for refresh address.

4164

64Kx1 bit DRAM chip

16 of this IC make the 128K RAM of the ZX Spectrum48 RAM.

e.g:NEC D4164C-3

Pinout:

NC
DIN
WE
RAS
A0
A2
A1
(+5V) VCC

1 °     16
2       15
3       14
4       13
5       12
6       11
7       10
8        9

GND (0V)
CAS
DOUT
A6
A3
A4
A5
A7