For those curious like myself (heavily elided for smaller wall of text):
The Z80-SIO (Serial Input/Output) ... basic function is a serial-to-parallel, parallel-to-serial converter/controller ... configurable ... "personality" ... optimized for a given serial data communications application.
The Z80-SIO ... asynchronous and synchronous byte-oriented ... IBM Bisync ... synchronous bit-oriented protocols ... HDLC and IBM SDLC ... virtually any other serial protocol for applications other than data communications (cassette or floppy disk interfaces, for example).
The Z80-SIO can generate and check CRC codes in any synchronous mode and can be programmed to check data integrity in various modes. The device also has facilities for modem controls in both channels, in applications where these controls are not needed, the modem controls can be used for general-purpose I/O.
What's really interesting is this bit:
• 0-550K bits/second with 2.5 MHz system clock rate
• 0-880K bits/second with 4.0 MHz system clock rate
110Kbps at 4MHz. That's almost the 115200 baud we're all familar with. At 4MHz! (2.5MHz yields 68750bytes/sec, or 67.13Kbps.)
---
For those curious like myself (heavily elided for smaller wall of text):
The Z80-SIO (Serial Input/Output) ... basic function is a serial-to-parallel, parallel-to-serial converter/controller ... configurable ... "personality" ... optimized for a given serial data communications application.
The Z80-SIO ... asynchronous and synchronous byte-oriented ... IBM Bisync ... synchronous bit-oriented protocols ... HDLC and IBM SDLC ... virtually any other serial protocol for applications other than data communications (cassette or floppy disk interfaces, for example).
The Z80-SIO can generate and check CRC codes in any synchronous mode and can be programmed to check data integrity in various modes. The device also has facilities for modem controls in both channels, in applications where these controls are not needed, the modem controls can be used for general-purpose I/O.
What's really interesting is this bit:
• 0-550K bits/second with 2.5 MHz system clock rate
• 0-880K bits/second with 4.0 MHz system clock rate
110Kbps at 4MHz. That's almost the 115200 baud we're all familar with. At 4MHz! (2.5MHz yields 68750bytes/sec, or 67.13Kbps.)
https://archive.org/download/Zilog_Z80-SIO_Technical_Manual/...
Also - rather amusingly, I discovered that the MK68564 datasheets ripped off the Z80-SIO's intro text verbatim. Are these compatibles or something completely different? https://www.digchip.com/datasheets/parts/datasheet/456/MK685...