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NOTE: When working with software handshaking the performance of the serial port is seriously reduced. When working at speeds of 9600 baud or above, the software handshaking will not work unless there is an intercharacter gap, ie. some time is left between the sending of each character. The gap allows the Z88 to catch up with serial operations, and without it the machine may loose characters.
After OZ 4.0, the driver has been seriously optimized to avoid such bytes lost. In 4.5, all the input put are unbuffered if no handshaking is set. It allows fast transfer up to 38400 bauds. To optimize speed transfer, three reason calls perform block transfer.
Serial Port Lines
The following table describes the 9-pin D-connector of the Z88:
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