software UART

The SWTPC 6800 computer system used a bit banger serial port based on the Motorola MIKBUG ROM monitor. It was limited to 110 or 300 baud. The I/O card (SWTPC MP-C) use a 6820 parallel interface. It was great when SWTPC released a new ROM that allowed for a real serial chip (6850) and you could get your TV Typewriter going at 1200 baud. I later used my MP-C card to interface to an IBM Selectric terminal at 134.5 baud. I had to convert the ASCII to IBM code in software anyway. Motorola MIKBUG http://www.swtpc.com/mholley/MP_A/MP_A_Index.htm SWTPC 6800 System http://www.swtpc.com/mholley/swtpc_6800.htm A 1978 picture of me at my Trendata 1000 Selectric terminal (IBM 2741 compatible). http://www.swtpc.com/mholley/MySystem/MySystemPhoto.htm Michael Holley www.swtpc.com ----- Original Message ----- From: "Richard Erlacher" <edick(a)idcomm.com> To: <classiccmp(a)classiccmp.org> Sent: Sunday, March 24, 2002 7:00 AM Subject: software UART