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Since the Ubicom SX instruction set is a superset of that of the Microchip PIC16C5X, see also my PIC page.
The information on this web page is based on my own experiences with the SX and SX-Key, both using them on personal projects and in the course of my employment. However, I am speaking only for myself, and my comments do not reflect the opinions of my employer, Ubicom, or other party.
Disclaimer: since August 2002 I've been an employee of Ubicom. However, nearly everything here predates that.
Code is available for:
There is a temptation to find the smallest values that seem to work, and then to back off somewhat. For example, I've found that at a setting of 50 ms, the SX-Key rarely reports errors. (Note that it sometimes reports programming errors even at the suggested 100 ms timing.) However, you should exercise extreme caution in your choice. I found out the hard way that just because the SX-Key doesn't report an error, doesn't mean that the part has programmed properly.
Some code I was debugging was behaving very strangely, and I just couldn't figure it out. Finally I tried increasing the programming time back to 100 ms, and all the problems went away!
Apparently it is not possible to verify the flash memory in the SX at the normal operating speed. If the flash cells aren't programmed long enough, they will read correctly with the long cycle time used in programming mode and by the IREAD instruction, but not at the full operating speed.
Scenix has published both the serial and parallel programming specifications for the SX; both are available from the Scenix Technical Support Specifications Page. Apparently they are considering publishing the specifications for the in-circuit debugging features as well, but have not yet made a decision.
| date code | revision | description |
|---|---|---|
| 9747, 9749, 9750, 9810, 9811, 9812 | 2.1 | won't work with debugger |
| 9814 | 2.4 | minimum revision necessary for debugger |
| 9818, 9819 | 2.4 or 2.5 (apparently there is no difference in the markings!) | |
| 9815, 9825, 9827, 9829, 9830, 9837, 9838, 9841, 9843, 9844, 9848 | 2.5 | comparator is disabled in sleep mode to reduce power consumption |
For more details, see Scenix's published errata.
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Last updated September 16, 2003 (but still woefully out of date!)
Copyright 1998, 1999, 2001, 2002, 2003 Eric Smith