I keep seeing these listed on ebay and I don't understand what role
they play in the HP HIL environment. Can someone enlighten me?
It's basically a dongle. It returns a unique number when it gets a
'Report Security' command. If the manual is to be beleived :
Byte Buts
1 7-0 Header : 0x10
2 7-0 ) Product (or exchange) part numbewr in biary. Byte 2
3 7-0 ) is least significat. Likely to be 46084 when converted to
4 7 ) decimal
4 6-0 Product letter (A) or least significant digit of exchange
identifier
5 7-0 } The 9 digit module serial number, ignoring the country letter
6 7-0 ) in binary. Bytr 5 is least significat. This will be unique,
7 7-0 ) apart from exchange modules
8 5-0 )
8 7-6 Reserved, set to 0
9 6-0 Serial number country letter
9 7 Reserved, set to 0
AS I understnad it, the first HP9000 machines (early versions of the 9826
and 9836) had no unique machine ID at all. Later ones, and things like
the 9816, hd a PROM on the CPU board that contaiend the serial number,
and was thus unique ot the machine. Software could read this number to
check it was running o nthe machine it was licesned for, and IIRC if you
repaced the CPU bord you transfered the ID PROM to the new board to
maintain the ID. Machiens with HP-HIL used these ID modules. If an ID
module failed, you might end up with an 'exchange module which gave the
same serial number but a different product ID (see byte 4). I believe you
then ahd to return your old ID module. Thus no 2 modules ever made gave
the excat same response, and no 2 modules in the field reported the same
serial number.
-tony