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How to toggle "Init" or "PaperFeed" pin on LPT port

How to toggle "Init" or "PaperFeed" pin on LPT port

How to toggle "Init" or "PaperFeed" pin on LPT port

      I need to toggle some pin (not a data signal) on an LPT port - but I can't write to an IO register to do it.

      Normal LPT ports have registers that can be used to control the port, but I have a USB to DB25 adapter which provides an LPT port but doesn't have a base-register (that I know of.)  Still, printer-driver-software must be able to wiggle control-lines - how is this done?
      We use a PC to control hardware during testing.  We can control a device using the data-lines from a parallel port (DB25) but the PC only had one parallel-port and we needed two.  I purchased a USB to DB25 adapter (SYBA) with the intention of controlling the device, however, this adapter doesn't behave the same as the native port.  With the native port, tying pins 11&12 to ground allows bytes to stream-out as fast as possible.  This doesn't work with the USB adapter - it wants to see transitions on one or more of the control lines.  I figured-out that if "Acknowledge" is toggled, bytes are "released".  So if I jumper, say, PaperFd to Acknowledge and toggle PaperFd, I'm good-to-go.


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