The Byte Back Modem doesn’t use the Z80 in/out ports; it uses logic gates to activate the 8251 USART, which is used to send and receive data. Reprint of the article from T-S Horizons.
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Experimenting With The Byte Back Modem
The Byte Back Modem doesn’t use the Z80 in/out ports; it uses logic gates to activate the 8251 USART, which is used to send and receive data. Reprint of the article from T-S Horizons.