20140618_log.md

Wed Jun 18 11:00:13 BST 2014

• Setting up bench

Wed Jun 18 11:25:17 BST 2014

• Testing servo on both models (connected to VBAT)
  • No problems encountered
• Testing servo + stepper
  • RPIO module has problems running both at once (not a HW issue)
  • But, using the lower-level API, ran both at once without issues
• Testing servo + stepper on battery
  • No issues

Wed Jun 18 11:53:55 BST 2014

• Looking at making design changes

Wed Jun 18 12:29:20 BST 2014

• Looking at firmware DC-motor issue
• Programming firmware with constant speed
  • encountered programming issues: resolved through removing motor connections and re-plugging programmer
  • no other issues: points to a comms problem
  • more programming issues: resolved through re-plugging programmer
  • encountered issue of not being able to power pi: everything turns off, short circuit?
    • attempted to power pi directly: no issues
    • re-connected pi and pibot-board: resets repeatedly on start
    • model-b pi has developed issue starting on either pibot-board, still starts fine of 5V direct
    • model-a does not have this issue

Wed Jun 18 14:04:03 BST 2014

• model-b power-up issue resolved by changing input from 5V: DC-DC cannot operate as 5V in to 5V out, needs to be different
• looking at firmware motor issue again
  • attaching UART cable and printing SPI to UART
    • servo moves when attaching serial and USB debounce fails
      • adding pull-up (4k7) on servo data line (up to 3v): servo jumps around less, still works
      • trying 10k pull-up: OK
        • adding pull-up to design
    • SPI is constantly reading 0 for all values unless written to

Wed Jun 18 18:02:45 BST 2014

• trying to fix SPI 0 read
  • avrdude gpio programming does not play nice with RPIO python module -- restart required
  • SPI interrupt vector (SPI_STC_vect) is triggering all the time