CCl!MUNICATIONS SECTION 6,7
6,7,9,3 Error 03: Response not matched by odd-even block count
6,7,9,4
6,7,9,5
6,7, 10
6. 7, 11
\/El!.V09F
The wrong positive acknowledgement has been given to a buffer,
despite confirmation requests.
Error 04: Retransmission rejected
Repeated transmission of a buffer gets only the NAK response,
has tried 10 times.
Error 05: No ENQ after WACK
Having sent out a WACK no acknowledging ENO has been received
for 5 seconds.
HARDWARE HANDSHAKING
This protocol is generally used with modems or modem simulators.
The use of RTS (Request to Send) and CTS (Clear to Send) is
therefore specified by the modem, particularly if half duplex or
two wire operation is desired (as on the public switched
telephone network). Both RTS and CTS may be deactivated as
usual,
If they are used, then the following takes place:
1) If HUNTER is not transmitting then RTS is inactive,
allowing the remote modem to transmit.
2) When starting a transmission buffer the RTS is activated.
Before transmission starts CTS is awaited from the modem.
When CTS becomes active HUNTER starts transmission.
3) During transmission RTS is kept active, but CTS is not
checked, if it became inactive the transmission would be
broken and synchronism dropped.
4) At the end of a transmission RTS is deactivated and HU~~ER
awaits reception.
There are no time outs on the hand shakes.
HARDWARE CONFIGURATION
The transmission channel could be the switched public network, 4
wire private lines etc.,
PAGE 6 - 38
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