There is a hardware problem with our implementation of an emulated parallel port. Typically when data, on a real PC, is sent to the parallel port, the signal to print is STROBE changing state, a parallel protocol signal line. We don't wait for STROBE, we immediately send the job to the print monitor. Some programs send data to the I/O port address designated for LPT1: but they don't pull the STROBE line low so nothing prints. Since we don't wait for STROBE to go low, it starts printing.
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