6502.org Forum  Projects  Code  Documents  Tools  Forum
It is currently Fri Nov 22, 2024 8:30 am

All times are UTC




Post new topic Reply to topic  [ 2 posts ] 
Author Message
PostPosted: Sun Oct 23, 2022 11:26 am 
Offline

Joined: Sat Mar 20, 2010 8:36 pm
Posts: 15
Location: Germany
Need help, need to delay the BE going high by at least 200nS after the RES line goes high. This is to force the W65C134 to use the external ROM from the start. I have proved that this works with using a pushbutton to hold the BE low till after the reset.

Any suggestions would be welcome.

I have attached the schematic for the W65C134SXB board that I am using.

Attachment:
File comment: W65C134SXB Schematic
W65C134SXB.pdf [35.49 KiB]
Downloaded 25 times


Top
 Profile  
Reply with quote  
PostPosted: Sun Oct 23, 2022 11:43 am 
Offline

Joined: Fri Jul 09, 2021 10:12 pm
Posts: 741
You could just use something like a DS1318 to hold it low, it will do so for quite a while though (100ms or more, I think).

You can also use an RC circuit through a Schmitt trigger to wait about the right amount of time.

Or feed your clock signal through a counter to count the right number of clock cycles for your delay.


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 posts ] 

All times are UTC


Who is online

Users browsing this forum: No registered users and 43 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to: