<p>More data from a 2nd printer (that didn’t have burned out 16v supply on two channels):</p>
Pin Voltages Dir Name Comment 1 0.0v Out ENC_A Encoder A Output 2 0.0v Out ENC_B Encoder B Output 3 0.0v Gnd GND Ground 4 1.6v In d 640 5 0.0v / 0.9v / 1.1v ? d 640 6 0.0v Gnd GND Ground 7 0.0v / 1.5v ? d 640 8 0.0v / 1.5v ? d 640 9 0.0v Gnd GND Ground 10 1.6v In d 640 11 1.1v / 0.9v / 0.0v Out d 640 12 0.0v Gnd GND Ground 13 0.0v d 693 14 0.0v d 540 15 3.3v Vcc VCC 3.3v for logic 16 0.0v ? d 693 17 16v In VINK_A Voltage for ink jets 18 16v In VINK_B Voltage for ink jets 19 16v In VINK_C Voltage for ink jets 20 16v In VINK_D Voltage for ink jets
<p>At this point, it’s very likely that:</p>
<p>4/5 and 10/11 are the same protocol (one for black, the other for color)</p>
<p>7/8 and 13/14 may be the same protocol, or different. But both probably use 1.5v signalling.</p>
<p>16 is either an enable or a clock.</p>
<p>More to come…</p>