> I see a similar behavior on the Entrega/PortGear device.
> Wayne posted a
> note a few months ago mentioning the behavior, so I'm guessing it's
> somewhere on his list to try and figure out why it happens.
>
Well, that guess is not quite right. The MK-1100 keyer uses the modem
control lines,
DTR/DSR/RTS/CTS for communications between WL and the keyer, while the
TXD/RXD lines pass through for rig control. The problem with most
USB-to-serial adapters is that they have very long delays between the
software interface that WL sees and the hardware DTR/DSR/RTS/CTS signals at
the ports. (The delay might be on outputs or inputs or both--it doesn't
matter.). Some are a few milliseconds, but some or hundreds of milliseconds.
For comparison, the delay in motherboard serial ports is less than about 1/4
msec--too fast for me to measure in software.
The protocol between WL and the MK-1100 is such that the data eventually
makes it through in spite of the delays, but too long to be useful.
The way WL handles those long delays can make WL's keyboard response "jerky"
(long delays in responding to keystrokes). I am considering modifications to
remove this jerkiness, but I can't do anything to overcome the delays in the
hardware.
Wayne
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