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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

(OP)
Hi,
      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.

Thanks!

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