uVM/PCB_History.md

Rev A

Prototype.

Issues

1. U2 - Incorrect pinout

   • Traces to pins 5-8 should be cut
   • Connect U2-5 to MOSI (U1-17)
   • Connect U2-6 to SCK (U1-19)
   • Connect U2-7 to VBat
   • Connect U2-8 to 5V

• U22/U20 - Layout error

  U20 and U22 share SER outputs with U1-4, this configuration is not usable.

  • Trace between U22-9 and U20-9 should be cut.
  • U21-10 connection to ground should be cut.
  • Connect U22-9 to U21-10.

• U2 - CS floating

  CS is not pulled high and is floating when not driven by U1. May interfere with flashing via ICSP.

  Connect U1-1 to 5V via 10K resistor.

• ICSP Header - Incorrect footprint used

  Pinout not compatible with standard ICSP header.

• R4 & R5 - incorrect value

  Use 270-330 Ohm instead of stated 10K.