TT083: Lukin programmable negative pulse generator

Uses ToprDAC8552BPSW to generate programmable pulses.  Output range is 0 to -7.5V into open load.

Two channels.  OUTA generates a negative pulse in response to a positive TTL input, and OUTB generates a negative pulse in response to a negative TTL input.

Uses ToprIsoDigInHS for the inputs.  Total latency about 100nsec.  I needed to slow the output down to control ringing and charge injection.

Processor is TipTop1590GRP (RP2040)

Arduino code:

Command protocol is standard E-Shop.  Commands are single letter followed by optional argument and semicolon. 

Processor echoes the command string, replacing ";" with "!" if the command was accepted, or "?" if not.

 Commands:
        Serial.println("Commands:" );
        Serial.println("D<arg>; sets DAC value.  Arg range 0 to 65535 (-7.5V into open load)" );
        Serial.println("d; returns DAC value" );
        Serial.println("S; stores DAC value into non-volatile memory" );