my new project.
UART universal for computers based on MOS65xx systems. To work the layout needs a chip with support for 8 bit port with handshaking. and 2 bit for control functions, and IRQ (not required) and RESET (not required)
The layout is based on the at89s4051 and MAX232 (for 220000 single bit/s)
Options for layout is:
Programmatically select the transmission speed for RS232 to 223400 bit/s
The FIFO for reading.
Support for XYModem.
Calculates the CRC and checks, indicating an error.
In-System Programming.
Easy installation without soldering
https://www.youtube.com/watch?v=7byqsQYUV1g&feature=youtu.be
and Ymodem on c64
https://youtu.be/WtvzV3p6meE

223,400 bps is not a standard speed. To what will you be connecting this device?

_________________
x86?  We ain't got no x86.  We don't NEED no stinking x86!

I suspect that this is a typo, and should be 230,400 bps.

Is the source for this project closed?