DIN Problem

[Thomas]

Hallo!

Board debugging no. 2354...

I have 5 DIN - shift registers.

That means 40 Button and 40 LEDs. (All 40 LEDs work.)

BUT: on the 3th shift register only Button 0-5 work and on the 4th only button 7 (pin 1F(Hex) 31(dec)) on the 5th DIN-shift register only Button 7 (pin 27(hex) 39(dec).

Electrical connetions seem to be ok. No short cuts or broken connection. 

Any Ideas how this can happen? Is shift register 3 damaged?

Other possibilities before heating the soldering iron and destroy a 74HC165?

[audiocommander]

Have you tried switching the ICs (eg. 2nd with 3rd), so you'd see if you got two damaged ICs. If it's the same result, maybe it's a coding error?

[Thomas]

I cannot switch the ICs...the only thing I can do is to remove them destructively.

(SO-package directly soldered) That's why I ask before I destroy them.

[audiocommander]

that could possibly be the reason: maybe they got destroyed by soldering too hot & too long :-\  It is said, that some ICs are very sensitive...

I think if there's no real good reason (eg AIN "purists"), sparing the 5ct for IC-sockets is actually no good idea...

have you tried testing with MIOSStudio? You can directly invoke DIN_PinGet() from the debug-interface (maybe you have to stop the User-Timer first). I have been very lucky for this handy interface when debugging my last DOUT struggles...

And if you're working with your own application: have you tried uploading a DIN-example app to see if that one is working? I had some strange errors in the past that were directly connected to some garbage in my code I have simply overseen.

I'd check that before desoldering the ICs.

;)

Michael

[Thomas]

Thank. Good ideas. I didn't think on the debug interface...

Btw. the oter problem with damaged code seems to be solved.

Don't know why and how. I only startet with a simplier application by commend some parts out and step by step decommand them.

And I use a new power connection where I could messure U and I.

Btw. flashing uses a little more current, but only some mA.