HP 34970A Data Acquisition Unit - communication protocol
In order to build a replacement display for the HP34970A data acquisition unit, I needed to understand the communication protocol between the CPU board and the front panel assembly.
General description
The unit is built with four boards:
- A1 is the main bard, with the PSU, the main controller and …
HP 34970A Data Acquisition Unit - part 4
After a summer pause, I'm back on my HP34970A replair project. In the previous post in this series, I've started to reverse ingineer the serial protocol between the CPU board and the fonrt panel, and implement a prototype of replacement display.
OLED display
I bought the bigest OLED display I …
HP 34970A Data Acquisition Unit - part 3
As explained in the previous post in this series, I've started to sniff the serial protocol between the main board and the display panel so I can replace the failed VFD by an OLED or TFT display managed by an arduino or similar.
Protocol
The serial communication takes place at …
HP 34970A Data Acquisition Unit - part 2
This is quick follow up of my previous blog post on my attempt to fix my recently acquired HP 34970A.
In my hurry to replace the failing FRAM (FM24C04) chips, I also replaced the FRAM chip on one of my 2 plugin modules.
Bad idea: the module then provoques an …
HP 34970A Data Acquisition Unit
I recently "scored" a HP 34970A with the DMM included and 2 plugin cards (HP 34901A and HP 34907A) for less than 200€. The plugins should be in working condition, but the main switch unit was almost "given" with the plugin modules since it is non functional.
It's in very …