74LS165

Testing/Troubleshooting
1

Hello, I tested my DIN module some weeks ago and it worked with 74LS165, thought some times it had problems but it had well worked a long time …

then yesterday I had to use it, replugged it … and nothing worked

Can It be the 74LS165 that don’t fit ? (normally its 74HCT165, I think that the logical voltages aren’t the same)

thanks

2

no idea ?

3

yes, no idea…

the 74LS165 should be ok, but I could also be wrong.

With the srio_interconnection_test you could at least ensure, that the connections to the module are ok

Best Regards, Thorsten.

4

no idea, what the problem might be..  :-\

I THINK 74LS165s should work - PIC I/O is both CMOS/TTL compatible.. so maybe some other issues? (Connections ect.)

Moebius

5

I had these same type problems when selecting '165s.  I found some 'LS165’s that would work and some that would not.  I’m thinking the ones that worked were from hitachi or toshiba… I finally gave up and went exclusively with 'HCs  no matter the manufacturer, they all seem to function correctly.

Of course, if possible, populate the boards with chips from the same company.

I have standardized on some that I can get locally… CD74HC165E 's from RCA.

good luck

gb

6

Could somebody please send me a non-working 74LS165 for evaluation?

Best Regards, Thorsten.

7

uhhh… i will happily sent you one… but I would think the shipping to Deutschland is about 100 times the cost of the chip.  maybe the spec should be changed to reflect the ‘HC’ version for klein bisschen mehr geld.  I can get the LS and HC versions in the US for the same price… approx. 45pfennig.

sorry if this dilutes the discussion

gb

8

Ok thanks for the informations

Mines are Motorola I think (little M inside a circle?)

I should test with HC, but i think my problem is a short on the board , I don’t see what it can be otherwise because it worked the first time …

Thorsten, If it’s really the fault of the LS chips (when i’ll test with HC) I’ll send you some

Thanks