upsilon/doc/hardware_notes.md

554 B

This document is for recording notes on measurements done on Upslion running on actual FPGAs.

Commit: 9c2731ad8d794d0b3c46999a40f0064f2b020c69
FPGA: Arty A7-100T
F4PGA commit: f43bb728b1bd9ef3807ef65bcf6b6629e0fa71f5

ADCs:

SPI clocks take about 10ns to start going up and down from low voltage. They rise to about 500mV in that time. MISO oscillates up and down up to 50mV with no data present, rising and stays at that until it oscillates down. Should not be a problem. Probably capacitance/crosstalk. Ringing of about 40mV on clock and SS.