• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

8085 Microprocessor system debugging

Status
Not open for further replies.

wonderz

New Member
Hello everyone

is there anyone with previous experience on 8085 systems?

I am facing a very confusing situation here.

we have made a two layer PCB for our 8085 system with single 8k EPROm and 2k SRAM . only chip select connectios are obtained using single thin soldered wires.

the system was working perfectly and efficiently for over a month untill we completed the whole project. yesterday as we were doing the finishing jobs after fitting it in box it stopped working. we could see a periodic signal on oscillocsope on A15,A14,A13,..,A8 the same signal was observed on all of them suprisingly the same exact signal could be seen on S0 pin 29. ( or S1 pin 33 I am not really sure about it now) It is so confusing how can the same signal appear on all of them? :roll:

could anyone suggest anything ? could it be due to one of the chip select soldered wires becoming loose while putting it in box?

I would appreciate any comment :wink:
 

McGuinn

New Member
Yes, or maybe capacitance has affected a floating input/output... Are all pull-up resistors installed?

Did you put it in a potting compound? I just am wonder about this as you don't seem to be able to reopen the box to check the wires manually???
 
Status
Not open for further replies.

Latest threads

EE World Online Articles

Loading
Top