Attendees
Action items
- Thomas Watteyne to write an nRF UART pass-through snippet
- Thomas Watteyne to write an VDDD tapping snippet
- Austin Patel to coordinate with Andrew Fearing to get 60x boards assembled with a regulator and an IMU
- Thomas Watteyne to work on letter for David Burnett
- Austin Patel to tell David Burnett turn-around time and cost for new board manufacturing
Minutes
Farnell order (60x XLs, 2x dev boards) should be received on
Will hold onto chips, just let me know where we should send it
Austin Patel will do!
DotBot runs!
BLE-based connectivity working
LH2: working on calibration using a calibration board (4x LH2 receivers)
FPGA: thanks David Burnett for point to https://github.com/PyFive-RISC-V/caravel_pyfive ! implements exactly what was needed, peripheral bus (Wishbone), DMA and HW acceleration
Kristofer PISTER great, as previous experience wasn’t fantastic with other approaches
VDDD tap: would prefer not haven’t an external regulator, breaks the vision a bit
we would like SCuM itself to work as a true single chip
do we get different results depending on the test (tapping a wire vs. using a power supply)
2 tests:
use a real wire
use the nRF:
pin to VDDD LDO out
high z, set 1, strobe from high z to active output, to high z, emulating tapping behavior
David Burnett it that doesn’t work, we can use a voltage divider
discussion about previous tests
tapped at 1.1V: @aus
test 1 leave tap connected, record whether programming works, optical programming, on McCoy with the IMU
test 2: remove tap when seeing program running
constant 1.8V didn't work; a tap at 1.8V didn’t work (board wouldn’t program)
Kristofer PISTER what did we do?
Fil Maksimovic program, doesn’t execute, tap, it executes
Kristofer PISTER looks like the only difference is the duration of the tap
Thomas Watteyne we could use the nRF to vary (sweep) the duration of the tap
Kristofer PISTER we need to get the nRF up and running, and try with the 3-wire bus
Austin Patel probably the next step is to use the nRF.
thoughts: people integrating on micro-robots may only need cold boot
low confidence this will work
looking to having the board work
Kristofer PISTER let’s
have Andrew Fearing put a regulator to get things going
study this with the nRF by disconnecting the regulator
Kristofer PISTER can we put a resistor divider on the board so voltage from nRF goes down to 1.1V
Austin Patel another pin which has the voltage divider, do can choose between straight to nRF, or voltage divider
Fil Maksimovic use a break-out board of a regulator?
Austin Patel will ask Andrew Fearing
Thomas Watteyne to write a UART pass-through snippet
Thomas Watteyne to write a strobe snippet
writing proposal