-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 source= http://www.piclist.com/piclist/2004/02/11/123903a.txt? Bob Blick says: >Now that is interesting. So program memory is not sacrificed when using >ICD on the smaller parts. >I'll stay tuned to this thread. Another question that I thought of is whether this is "memory" or a "register," i.e. does it persist after power down. I haven't tested. At a cost on only 26 or so hours, I have edited the .hex file so that it is more readable by people. For example, I replaced the phrase "0800" with the phrase " return," and so forth. I am certain that I understand how it works, have control over it, and can use it to do other things. I decided to email a permission to publish request letter to tech.support@microchip.com, just to be clean, and I haven't uploaded this file. When my ISP is back up :-( I will reconcile my web site and Microchip's response. Has anyone pursued "permission" from Microchip, and are there contacts you might mail me privately? It turns out that the code is almost exclusively dedicated to read / write single bytes which are accessible via FSR and INDF. No program or EEPROM memory is touched. This, of course, answers my earlier question about modifying data RAM. The dispatch table has 26 entries, but most of them jump to "Send_NAK" The most curious thing that I found was that they use 16H bytes of code to save an image of the STATUS register. One thing they do is to copy STATUS (arbitrary bank) to STATUS (bank 3). Although this seems odd, the on chip debugger document does say that the high and low PORTB registers act differently. Seen against the tight code space, this effort seems significant. They also have a macro to "call" a routine and "return" without affecting the hardware stack, and only consuming 1 RAM location (all in same code page). - --- Aubrey McIntosh http://www.piclist.com/member/AM-vima-Y84 PIC/PICList FAQ: http://www.piclist.com -----BEGIN PGP SIGNATURE----- Version: PGPfreeware 7.0.3 for non-commercial use iQA/AwUBQCrLkgKlSw8yssF7EQLMjQCfSQ6IVN/w1aRSFFDqwFA5k/7t/qgAnRNc PS847lRioehAZLd6qfhWUKW1 =DFjO -----END PGP SIGNATURE----- -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads