odd thing..
(03-24-2023, 06:56 PM)admin Wrote: You SHOULD be using AT&K1 with anything over 2400 baud.  AT&K0, AT&K2, and AT&K3 all turn OFF the hardware flow control.  You WANT that on for your BBS.  Without the hardware flow control, you will have errors sending any large chunks of data when the receiver is telling the sender to stop sending data.

(From the WiModem232 PDF)

AT&K[x] – Get/Set hardware flow control mode [0/1/2/3]
This command will change the hardware handshaking mode. 0 = off, 1+ = on. Default is 0

Jim, just wondering...with the next revision of the WiModem232 PDF, could you change the above entry to:

"0 = off, 1 = on, 2 = off, 3 = off", or something like that, to make it perfectly clear for simpletons such as myself? Smile

Reading the original entry I absolutely took it as 0 turned it off and everything else turned it on.

I checked the code and only K0 turns off the hardware handshaking, so the manual is correct.
Okay, so then when I had it set to K3 it was turned on.

What's the difference between K1, K2 and K3 then, if all of them turn hardware handshaking on?

Nothing is different. K2 and K3 are supported only so that they don't return error messages. They all do the same thing.

Every modem manufacturer treated these differently. AT&K1 is RTS/CTS, unidirectional (which makes no sense to me). Here is the actual list of Hayes commands for AT&K:

AT&K0 - No flow control
AT&K1 - Enables unidirectional RTS/CTS hardware flow control.
AT&K2 - Enables unidirectional XON/XOFF
AT&K3 - Enables bi-directional RTS/CTS hardware flow control.
AT&K4 - Enables bi-directional XON/OFF
AT&K5 - Enables transparent XON/OFF
AT&K6 - Enables both RTS/CTS and XON/OFF
AT&K7 - Enables bi-directional DTR/DSR hardware flow control.
AT&K8 - Enables unidirectional DTR/DSR hardware flow control

I only support either no flow control or bi-directional flow control using AT&K1, AT&K2, or AT&K3. I don't see a need for XON/XOFF flow control (I have never had anyone even ask about it).
Okay, I think this clears things up (for me).

If I use "AT&K0", hardware handshaking is turned OFF.

If I use "AT&K1, AT&K2, or AT&K3", then hardware handshaking
is turned ON, enabling bi-directional RTS/CTS hardware flow control.

Thanks for the explanation Jim. Smile
You are correct!

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