Maker Pro
Maker Pro

Safety critical RF remote control protocol?



Jan 1, 1970
Coupled remote control with main unit. Both ends are transmit and receive
using Nordic semiconductor nRF905 tx/rx chip sets.
The synchro routine seems to work , requiring 2 way link both ways, to
synchronous codings between both units. But whatever button is pressed ,
opens up the serial data line on the main unit , but non varying with
whatever button is pushed.
Uses Atmel ATMEGA68 uC on the hand unit and 2 x ATMEGA168 on the main unit .
One probably for synchro and decoding functions and the other for opening
out/monitoring to/from the controlled operations. Otherwise uses 4066 and
ULN2003A to buffer out to relays and powerfets for pulsing/speed control. So
pinouts available for all ICs involved
Is the failure likely in the decoding / fanning-out operation or some
feedback monitoring signal not getting to the main unit Tx as
How to narrow down to which, no schematic available, and thick conformal
coating over SM does not help