HP 16700 - MC68000 probe (E2477AA) UDS/LDS delays

[philpem]

Hi,

Does anyone know how much the HP E2477AA (https://literature.cdn.keysight.com/litweb/pdf/E2447-97002.pdf) probe delays the UDS and LDS signals by?

I'm planning to probe a 68000 system but I need to build an adapter as the E2477AA is for PGA parts and this is a DIP-packaged 68000. To do this I need to know what the HP probe does. HP specified the wiring, but not the delay on UDS/LDS.

Thanks
Phil.

[TK]

Why not you use the standard HP / Agilent logic analyzer POD for probing the 68000? 

http://literature.cdn.keysight.com/litweb/pdf/16760-97016.pdf

[DaJMasta]

Does it actually matter?  I'm seeing 68000 series parts to 200MHz or so, which means even the fastest buses can tolerate a couple inches of copper worth of skew or delay.


That is, unless you're using your LA with a pattern generator as a full ICE, where the distance would count for a lot more because you are also injecting signals.  If you're just monitoring pins, it shouldn't be of any concern how the delay is unless you're synchronizing to an external source, in which case you just need the offset from it.

[philpem]

Why not you use the standard HP / Agilent logic analyzer POD for probing the 68000? 

http://literature.cdn.keysight.com/litweb/pdf/16760-97016.pdf

1) Because they don't come up for sale often
2) Because you can't use them with the DIP-packaged 68000, unless you have the adapter - which was a bloody expensive Emulation Technologies custom job.

Does it actually matter?  I'm seeing 68000 series parts to 200MHz or so, which means even the fastest buses can tolerate a couple inches of copper worth of skew or delay.

That is, unless you're using your LA with a pattern generator as a full ICE, where the distance would count for a lot more because you are also injecting signals.  If you're just monitoring pins, it shouldn't be of any concern how the delay is unless you're synchronizing to an external source, in which case you just need the offset from it.

The probe pod delays the data strobes slightly - I assume this is to guarantee setup/hold times on acquisition.

So the question is, how long that delay needs to be. I can make an educated guess at a few nanoseconds (i.e. a pair of 74HC04 gates), but it'd be nice to know the real number.

[gslick]

Do you have a E2477AA 68000 preprocessor and you have some questions about it, or do you not have one and you are considering building an equivalent?

I have 10311B (64670A) 68000/68010 preprocessor that attaches to a 10269C for use with DIP-packaged 68000/68010. I don't have a service manual with schematics for it, but if there are some questions about it that could be answered by visual inspection I could take a look

[philpem]

I'm trying to build a functional equivalent -- as I said above, I can't get an E2477AA, but I do have a bunch of the 01650-63203 transition adapters.

There isn't a schematic set for it, as far as I'm aware. Just the operations manual. As far as I can tell the repair procedure was "buy a new one".