SX chips date code: need do identify old or new chips

Eduardo G

SX-Key development system documentation explains:

"This manual is written for the SX20/28 chips with a date code of AB9921AA or later, and SX48/52 chips
with a date code of AB0001A or later.
Older chips are not supported by this manual or the SX-Key development system."

I've received an offer of hundreds of SX28 from a local dealer. These chips are labelled with the Scenix logo. Then I want to verify the date code of the chips, will I be able to program them witn my SX-blitz (revision A)?. Is the date code (AB9921AA or some similar) encoded in some string of the chip label?

Thank you in advance

Ken Gracey

Hello Eduardo,

There was a period of time in the early SX production [noparse][[/noparse]which I remember] that involved changes that affected debugging and/or comparator functionality. This was probably back in 1997 or so. My recollection is that there were very few of these on the market. That was a long time ago and memory fades.

Scenix used a more extensive date code as you pointed out. This date code should be printed on the chip package, most likely silk-screened (not laser printed, like the Parallax versions).

Ask the supplier for the date code on the chips, post it here·and I'll research our files for more information. It's possible that they'd program but not debug, in which case the SX-Blitz should work. Whatever you do, get a handful of them before you buy the whole lot.

Better yet, spend a few extra dollars and buy them from Parallax and you know they'll work.

Sincerely,

Ken Gracey
Parallax, Inc.

Phil Pilgrim (PhiPi)

I'm not sure if this will help or not, but I found an old Parallax errata sheet that contains some chip-specific info. I've attached a copy below. Also, the last SX18 chips I used in production had the following code:

····SX18AC75/DPES
····AB9931AB

As I recall, they worked to spec with my Rev E SX-Key without the need for workarounds. Although the SX28 and SX18 silicon is the same (I believe), these post-date the ones you've been offered by ten weeks and seem to carry a different rev code.

-Phil