[volt-nuts] HP 3458A Error message "RAM TEST 1 HIGH"

[Frank Stellmach]

Hello John,

just a guess, as that special error is not documented anywhere:
One of the nonvolatile RAMs seems to have reached its battery end date. 
(10-15yrs.)

I assumeink, it's one of the two 32kx8 RAMs, which store general 
instrument settings, as both are organized as HIGH and LOW byte of a 
16bit word (see CLIP).
And you are getting no additional CAL Error, which would indicate, that 
the singular 2kx8 RAM would be affected.

(I assume, your instrument stil has the three DALLAS RAMs with 
moulded-in batteries)

The instrument continues working, because false data in the settings can 
be ignored; perhaps it simply clears the settings and resets the 
checksum, other than in the case of the CAL Ram.

Anyhow, if my guess is right, about the 10-15yrs. old datecode on the 
RAMs, it's high time to download/save the content of the CAL Ram, and to 
buy new RAMs for replacement. (See comment from Poul-Henning about 
undocumented commands)

Frank