This is a summary of the signals on the 40-pin 3870 “F8” CPU chip in the Fluke 8050A multimeter. It's intended primarily as a reference while wiring up the interconnects from this CPU to the STM32F103 microcontroller.

Signal 3870 Pin 3870 Pin Signal
Vcc/+5 40 1
39 2
38 3 RNGA
Z 37 4 RNGB
Y 36 5 RNGC
X 356 FB
W 347
338
329
3110
3011 ST4
2912 ST3
2813 ST2
2714 ST1
2615 ST0
2516
2417 FD
HV 2318 FA
DP 2219 FC
2120 GND