Quick update on the jGPS board from Tuesday:

- We found a bunch of stupid things that we fixed, including:
   -  an incorrectly wired capacitor that caused power supply bouncing
      on 1.8V
   - Several mis-valued components in the BOM, most egregiously the
     CPLD variant which we had to swap out.

- We fired up the board, programmed the STM32, boot up the Ethernet
  connection, and then streamed NMEA data from the Venus638 COTS GPS
  receiver. GREAT NEWS here - after about a minute of walking outside,
  it locked! So our RF system doesn't totally suck, which is great.

- That said, we're having serious issues with the SkyTraq Venus638. It
  turns out we don't understand this chip, or it's buggy, or their
  Windows-based programming software sucks, or most likely some
  combination of these three things. Switching to binary mode, the chip
  stopped responding so now we have to figure out how to "unbrick" it.

Next up:

- Get the MAX2769 up and running.
- Verifying the data path from CPLD to STM to Ethernet.
- De-brick the Venus638.


-- -------------------------------------------------------
Andrew Greenberg

Electrical and Computer Engineering
Portland State University
a...@ece.pdx.edu  C: 503.708.7711

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