multiple RAM contents

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digitalman
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Joined: Tue Sep 17, 2013 9:49 am

multiple RAM contents

Post by digitalman »

Hello,

Does LogicCircuit support multiple RAMs on the sample circuit? It seems that when I load data into one RAM, all other RAMs are being loaded with the same data. Is there way to handle multiple independent RAMs in the same circuit? Or, am I missing something? Thanks!

v/r,
Long
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admin
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Re: multiple RAM contents

Post by admin »

Yes it supports multiple RAMs and ROMs. If you have some problems please upload your circuit here or send it to me in email and I’ll have a look.
digitalman
Posts: 16
Joined: Tue Sep 17, 2013 9:49 am

Re: multiple RAM contents

Post by digitalman »

The multiple independent RAMs does not seem to work for 'Persist memory between runs' setting. All other settings work. I need to use 'Persist memory' in order to load the RAM content before the simulation. Otherwise, it'll be tedious to load each RAM by hand during simulation. Any idea to support loading RAM content without using 'persist memory' setting? Thanks!

v/r,
Long
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Re: multiple RAM contents

Post by admin »

What probably is happening is you have a sub circuit where you have your RAM with persisting memory. If you happened to have multiple such sub circuits used in your main circuit than after the power goes off it will need to write multiple instances of memory to one RAM. This is impossible of course.
So the program does not write memory state back in this case.
What you can do is to move such RAMs on the main circuit.
Please let me know if this is what you experiencing.
I’ll need to update the help page to reflect this. Somehow I missed it.
digitalman
Posts: 16
Joined: Tue Sep 17, 2013 9:49 am

Re: multiple RAM contents

Post by digitalman »

That was exactly what you described. I created a chip that contained a RAM. Then, I reused the same chip multiple time in the main circuit. With persist ram setting on, the program will block power on to the circuit. To fix the problem, I make multiple copy of the chip and give them different names. And it works perfectly. Thanks again for pointing the right direction!

v/r,
Long
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