Got a UART? It will make the Kaypro keyboard output into parallel without
changing a thing. The signal's 300 baud RS-232 at TTL levels.
Bob Maxwell
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Hi Bob! Thanks to everyone who replied to my question. They have been very
helpful.
The goal of this project is to interface the Kaypro II serial keyboard to a
Vector Graphic Flashwriter II video board. It requires 8 bits of parallel
input (TTL levels) and a strobe. It provides +5v and ground connections.
The interface is 8 bits of data, 1 strobe line, +5v, and ground connected to
an intel 8212 parallel interface chip.
Does anyone have a schematic for *simple* hardware only circuit using a
commonly available UART, like an 8251 or 8250, to do the serial to parallel
conversion? I am looking for a schematic which I can easily modify to strap
the UART to 300bps operation.
Really, I'd like to stress a *simple* circuit using a small number of chips
and discrete components on a small protoboard. Preferably with +5v only
operation. Even a hand drawn example or one in a datasheet would be great.
I have searched on the internet for a simple circuit but have not found
anything I could use.
Please no MCU's or programmable devices, I realize how appealing they are
but they require learning time consuming programming environments and I am
pressed for time at the moment.
Thanks in advance for any help!
Andrew Lynch
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