Re: GPIB board for calibrating AM503B, or alternatives?
Hi Rico,toggle quoted messageShow quoted text
Since Tek did not provide any support information in the manual for the AM503B I was hoping you found out even more about the internals than this little bit of information.
I am also very interested in knowing exactly how you did this so I can replicate the procedure.
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Rico Sonderegger
Sent: Sunday, May 09, 2021 6:47 AM
Subject: Re: [TekScopes] GPIB board for calibrating AM503B, or alternatives?
I have 3 of these GPIB adapters (have 3 x AM5030B).
I wanted to program the serial number and it didn't work. So I connected a logic analyzer to see what was going on.
If you only want to update the calibration data, you can use the addresses 0xE0-00xE1 (CALC 00 or RinX1 value), 0x0B-0X0C (CALC 01 or RinX10 value) and 0xCA-0xCB (CALC 02 or RinX100 value) on the I2C bus to program the new values in the PCF8570 (base address 0XA0) using a "Bus Pirate".
The calibration data are stored there. After changing the battery, there is 0x61A8 (= 25000).
Dennis Tillman W7pF