Newbie: Problem with rom

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asdf
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Joined: Tue Jul 23, 2019 11:42 am

Newbie: Problem with rom

Post by asdf »

I have made a 4 bit counter which cycles from 0000 to 1111 and I want to use this to cycle through rom addresses. The problem is that however i try to connect it it gives me bit length errors
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admin
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Re: Newbie: Problem with rom

Post by admin »

You can use splitter: https://logiccircuit.org/splitter.html
Also I'd recommend to read help pages at: https://logiccircuit.org/help.html
asdf
Posts: 2
Joined: Tue Jul 23, 2019 11:42 am

Re: Newbie: Problem with rom

Post by asdf »

If I connect (on the address side) a splitter with 4 split pins and 4 bit width it gives the error that the counter and splitter have different bit widths however, if i use one with 4 split pins and one split pin bit width it gives the error that not all address bits are connected. Could you please post an example for how you would use a splitter?
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admin
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Re: Newbie: Problem with rom

Post by admin »

You can look at any sample files from the download section.
What you need to do is double click your ROM and check how many bits in the address. Alternatively just hover mouse over any pin on the circuit symbol side and it will show you bit width and all the other information. Them just make sure the bit widths match.
Max5923
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Joined: Thu Jan 09, 2020 1:40 pm

Re: Newbie: Problem with rom

Post by Max5923 »

I know!
The problem is that you had the input width as 4 and thought it was the output. The output width is the sum of all the widths it was input-ed.

Another weird thing is that the output can serve as an input, so you can get every single bit of a higher bit width for operation on it.

This should fix your problem.
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