How to Read and Write Data to the 2K8RAM in NI Multisim

[Tien_P]

Overview

The 2K8RAM is a memory component that lets you write and read 8 bit data; it has 4096 memory addresses where you to store your data. This component is a core model as part of the XSPICE simulation engine and this example shows how to write and read data to this component.

Description

The pin out for this component is as follow:

D0 -D7 - Digital inputs

A0 - A11 - Addresses

WE - Write when high and read when low

CS - Address select

Q0-Q7 - Digital outputs

In this example, two bits data will be written to D0 and D1 and address A0 and A1 are used, the remaining digital inputs and address pins are set to low constant. The data in the table below was entered into the Word Generator. Since this part does not have a clock, between each state you should add set all inputs to 0.

CS	WE	A0	A1	D1	D0	Description
1	1	0	0	0	1	Write 01 to address 00
0	0	0	0	0	0	Next clock cycle
1	1	1	0	1	0	Write 10 to address 01
0	0	0	0	0	0	Next clock cycle
1	1	1	1	1	1	Write 11 to address 11
1	0	0	0	0	0	Next clock cycle
1	0	0	0	0	0	Read data from address00
0	0	0	0	0	0	Next clock cycle
1	0	1	0	0	0	Read data from address 01
0	0	0	0	0	0	Next clock cycle
1	0	1	1	0	0	Read data from address 11

Steps to Implement or Execute Code

To run the attached example circuit do the following:

1. Double-click the Word Generator to expand the interface
2. Right-click on the first row of binary data and select Set Cursor in the context menu
3. Click the Step
4. Select Simulate»Run or click the Run icon
5. Click the Step button to step through the data, wait for the probes connecting to WE and CS pin to change state before you click Step again

Requirements

Software

NI Multisim 13

Hardware

Additional Images or Video