CrumProg HP chip driver

This Bus Driver designed to connect Cartridge chip from Hewlet Pakard printer to programmer CrumProg.

The Step Up converter generate the 8 volt from 3.3 volt of CrumProg to drive the bus signals. Chip transmit information by changing its consumption current. Host send information by voltage switching.
The comparator measure the chip consumption current and convert it to output pulses.