Teardown of a Cadex C7000 battery analyser.
Dave, curious where this came from, since you said it was 110V I assume it was shipped from NA?
They still list the C7000 on their website:
https://www.cadex.com/products
Back in the 90's all of the serious cellular phone shops in my area had a Cadex unit to test batteries. They were pretty useful, especially in the NiCAD and NiMH days. They were also quite common in the 2-way radio rental and service dealers.
Chances are there is a 10 bit ADC inside the PIC.
Just a guess: 4 of the resistors are used as load for discharging, and the remaining 3 are used during charging, to balance multi-level cells.
Set a C7000 battery analyzer for stand-alone use
1 Press the MENU key on the C7000 battery analyzer.
2 Press ▲ or ▼ to scroll to SYSTEM SETUP (on the analyzer display screen), and then press ENTER.
3 Press ▲ or ▼ to scroll to OUTPUT DEVICES, and then press ENTER.
4 Press ▲ or ▼ to scroll to SERIAL PORT DEVICE, and then press ENTER.
5 Press ▲ or ▼ to scroll to any setting other than BATSHOP, and then press ENTER.
6 Press ENTER again to confirm your selection.
7 Press ESC twice to return to the global display.
The latest C7000 firmware V3.53 can be found here
http://www.ko4bb.com/getsimple/index.php?id=download&file=06_Misc_Test_Equipment/Cadex_C7000_Battery_Analyzer_EPROM_3.53.BIN
I have newer version c7400-c, need firmware 3.xx does anybody have?