hello kubeek?

 

CS2 is an active high chip select and might need to be ties high. Check the datasheet.

One other point. Most devices are not great at sourcing current when they are high. So driving a LED connected to ground may be a problem. The data outputs of the RAM chip will probably prefer to grond an LED and resistor connected to VCC. Again this information is in the datasheet.

The symbol might be called Iol for current with output low or Ioh for current with output high. On a CMOS device these two numbers should be the same. On older NMOS or TTL devices the Ioh number might be orders of magnitude smaller than Iol.

Lastly have some patience. Datasheets are written for engineers, and they don't develop the ability to read them overnight. It is why they go to school for a couple of years to get a degree. That you want to do what you are doing is commendable, but remember "Anything worth doing is worth doing well"

 

Can someone PLEASE post the correct schematic for this memory device, i have tried everything and cant get it to work, please....im on my knees know

 

There is a possibility that you may have problems with the memory IC tied straight to the data bus. In the 8 bit days, we used a "bus buffer" or octal tranceiver to reduce loading on the microprocessor's data lines.

Look up a data sheet for a 74LS245. The original interpretation of the S/R^ signal was Read/Write not, just to make the function less mysterious. Unless you have multiple devices sharing the data bus, you can just tie the CE^ pin low.

 

There is a possibility that you may have problems with the memory IC tied straight to the data bus. In the 8 bit days, we used a "bus buffer" or octal tranceiver to reduce loading on the microprocessor's data lines.

Look up a data sheet for a 74LS245. The original interpretation of the S/R^ signal was Read/Write not, just to make the function less mysterious. Unless you have multiple devices sharing the data bus, you can just tie the CE^ pin low.

No, the schematic posted shows what i have tried. Nothing else uses the bus, just the memory.
Also, do i have to pull down the bi direction pins because they are tristated, can they not be left floating?
Before you ask i currently pull them down...

 

No, the schematic posted shows what i have tried. Nothing else uses the bus, just the memory.
Also, do i have to pull down the bi direction pins because they are tristated, can they not be left floating?
Before you ask i currently pull them down...

You mean those LEDs aren´t actually there?

 

You mean those LEDs aren´t actually there?

Yes they are but nothing else is on the bus

 

Looking at the datasheet, write should be done like this:
1. address
2. CE and WE 0
3. Data need to be valid
4. WE and CE to 1
maybe the CE can stay at 0, not sure from the datasheet

read:
1. address
2. CE to 0
3. OE to 0
4. data should be at the outputs
be sure to have the swithes OFF before reading data, or you will blow the outputs
What current do the leds use? double check the data switches to be sure they are disconnected from the outputs

 

when you say blow the outputs you mean, damage them? =O

 

I mean destroy them

 

destoy the LED or chip....

 

If the switch merely turns the led on or off, then the only other thing the switch can destroy is the chip. Just try the write-read process properly and see if it still works.

 

Yo kubeek..

Im drinking alot of shandy, do you know why...

You are amazing, IT BLOODY WORKS!!!!
TO KUBEEK!!!!!