> Are you saying that when you use the converter
> handshaking is required but when Olin used the same converter 
> he did not need handshaking?

The other way round. I use that converter, without handshake
connections, and I have no trouble. Olin has trouble, which is at least
partly cured by adding the hardware handshake loopbacks.

But my bet is that the PC drivers make the difference.

> Clearly, either the communications software or the hardware 
> can determine if hardware handshaking is required.

hardware == usb-serial converter? it should not decide that HW handshake
is needed!
hardware == the connected serial gadget? Neither my Wisp628 nor Olin's
EsayProg uses hardware handshake.

> I'm simply 
> saying that it is
> not unheard of  for computer (DTE) RS-232 interface hardware 
> (UARTs) to
> require handshaking regardless of the communications software 
> using the
> interface.  Two examples of this behavior are the Rockwell 
> R6551AP UART chip
> and probably the original IBM PC RS-232 adapter card as 
> specified in the
> legendary "Blue Book."

Maybe there is hardware around that requires this, but the original PC
hardware used a UART that was fully programmable by software, the
handshake lines were simply bits in the interface that the software
could use as it saw fit. Definitely no requirement by the hardware to
use these lines!

Wouter van Ooijen

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