First, I implemented the cycle of 6 combinations of switching signals: A_H, A_L, B_H, B_L, C_H, C_L in loop using delay time before switching to next combination. All as explained here: http://www.edn.com/design/sensors/4407580/Brushless-DC-Motors-Part-II--Control-Principles
And the brushless motor rotates! I'm happy!
No I want to implement combinations switching algorithm using ADC_A, ADC_B, ADC_C and ADC_CENTER signals. I expect to see 60 degree shifted ADC_A, ADC_B and ADC_C while ADC_CENTER is constant. But when I look for that four signals using oscilloscope I see that they are all the same!!! Why? Where is the mistake? In schematic or may be in soldering ( how to check it )? Explain me please! Schematic is taken from here: https://raw.githubusercontent.com/frank26080115/Frank-Synced-BLDC-ESC/master/circuit/ckt_preview.png
It happens at every step when I switch from one Low Side shoulder to another( A_L, B_L, C_L ). Could it be the reason that the Low side shoulders I drive using simple gpio outputs, not PWM signals? On steps when I switch High side shoulders that driven by PWM signals there is no any voltage peaks.
I found the causes of voltage surges on ADC channels - there is to long delay between switches to next state. The delay is necessary to exclude the probability of opening of the two MOSFET of one phase at the same time. As it turned out, I chose too much delay. Reduce delays and surges missing.