9 Nov
2022
9 Nov
'22
2:21 a.m.
On Wed, 9 Nov 2022, Steve Lewis wrote:
always imagined it would be possible to "bit
bang" across these external IO
pins with some PALM-assembly -- the machine should be fast enough to encode
7-bit ASCII at 300 baud across those pins, maybe 1200. I'm not sure if
The PALM and thus the 51[012]0 is much much faster than that (I guess
about 0.7 MIPS).
I do bit-banging on the Asynchronous Serial I/O card with twice the baud
rate (to sample the center of a bit) and am able to do *full-duplex*
communications *with* terminal emulation *and* character set conversion at
4800 baud.
Using the byte mode of the I/O adapter I can go up to 38400 baud (used for
file transfers).
Remember: this card is absolutely dumb, it essentially only has shift
registers and a clock generator. The benefits come from the zero-overhead
interrupt context switches and the great number of fast processor
registers.
But back to your questions: I personally have never heard of these
products. I only know that there was a third-party hard disk option.
Christian