Hello, I compared the content of firmware 8 from my own HP3458A with the latest firmware 9. Changes of firmware 9 over FW 8 is nowhere documented by HP - that's strange. On the agilent forum, no one of the agilent guys wanted to respond to my question about that version.. So I was even more curious, what's the content of the change, and if it makes sense to update to the new version. I did a low level comparison, just byte by byte over all 384k. It turns out, that 10 bytes only are different, 4bytes of them I assume being 2 basic absolute jump addresses at the end of the EPROM like RES, IRQ, NMI, or so. One byte I assume to be referenced to the idn? GPIB command, as it is located directly before the HP3458A identifier string. Perhaps that has something to do with the change of name from HP to agilent. As I'm not familiar with the 68000 processor, I did not attempt any disassembly of the code. It's quite obvious, that no functionality change or important correction of bugs happened. Therefore, I will not update the firmware in my instrument. I assume, that in this version, perhaps those undocumented commands MREAD, MWRITE have been blocked, by changing their entry addresses in the command parser. Perhaps somebody from the volt-nuts list can analyse better those different bytes?! Frank Compare firmware.bin and firmware_rev9.bin... Difference @ OFFSET 553 File1 = 8 File2 = 9 Difference @ OFFSET 1FFFF File1 = AA File2 = AB Difference @ OFFSET 4E21C File1 = FD File2 = 1 Difference @ OFFSET 4E21D File1 = 1C File2 = DC Difference @ OFFSET 4E223 File1 = 8C File2 = 8D Difference @ OFFSET 4E224 File1 = D1 File2 = C1 Difference @ OFFSET 5FFFC File1 = 2B File2 = 2A Difference @ OFFSET 5FFFD File1 = 79 File2 = 7A Difference @ OFFSET 5FFFE File1 = B2 File2 = A6 Difference @ OFFSET 5FFFF File1 = 98 File2 = 59 10 Differences

In message <52DBEB8F.90705@freenet.de>, Frank Stellmach writes: >Compare firmware.bin and firmware_rev9.bin... >Difference @ OFFSET 553 >File1 = 8 >File2 = 9 Version number of mainboard firmware >Difference @ OFFSET 1FFFF >File1 = AA >File2 = AB Checksum, low eprom, first pair >Difference @ OFFSET 4E21C >File1 = FD >File2 = 1 >Difference @ OFFSET 4E21D >File1 = 1C >File2 = DC >Difference @ OFFSET 4E223 >File1 = 8C >File2 = 8D >Difference @ OFFSET 4E224 >File1 = D1 >File2 = C1 This changes two limit values from a difference of 120000 to 245760, in what I belive is a part of the selftest code. >Difference @ OFFSET 5FFFC >File1 = 2B >File2 = 2A >Difference @ OFFSET 5FFFD >File1 = 79 >File2 = 7A Checksum, high eprom, last pair >Difference @ OFFSET 5FFFE >File1 = B2 >File2 = A6 >Difference @ OFFSET 5FFFF >File1 = 98 >File2 = 59 Checksum, low eprom, last pair -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.