Topics

#Homebrew #Homebrew

btrenkoski@...
 

Hi all,

I'm trying to build an 1802 based computer, inspired by Pecom64, which is computer produces in country where I was born.

I have problem latching with CDP1852 chip. The one I have is Harris.

The problem is that when input data is less then 16DEC (or 10Hex) it does not set SR flag. If data is greater then 10HEX everything works fine.

I have 4 chips, 2 of them are CDP1852CE and other two are CDP1852E, and have the same problem with all of them.

I am using N0 as output, and can confirm that it is properly set, and also voltage is good enough.

Any idea what can cause this problem? BTW I am using CDP1852 as output only.

Thanks,
Branko

btrenkoski@...
 

Found what was the problem.

CLEAR line was not connected. Set it to HIGH solve the problem :)