Tainet T-288C, Руководство пользователя

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AUXILIARY SUMMARY FOR FAX FUNCTION A3-5
A3.3.6 HDLC Receive, +FRH=<MOD>
The cFRH=<MOD> causes the DCE to receive HDLC framed data using
the modulation mode selected in <MOD>, and deliver the next received frame to the
DTE. <MOD> may have the values shown in section 1.1.
If the DCE detects the selected carrier with an HDLC flag, the DCE shall send the
CONNECT result code to the DTE. The DCE will return to command state upon loss
of carrier, sending the NO CARRIER result code to the DTE.
The DCE strips flags, and receives and buffers frames. The received data, starting
with the first non-flag byte and continuing through the last FCS byte shall be
transferred to the DTE. The DTE should ignore the value of the FCS bytes. The DCE
performs HDLC zero-bit deletion and error checking.
After the FCS bytes are transferred, the DCE shall mark the end of the frame with the
characters <DLE><ETX>, and report the status of the frame reception to the DTE:
If the frame was received correctly (FCS is OK), the DCE shall return the OK result
code.
If the frame was received in error (FCS is not OK, or carrier lost, or data lost due to
data overflow), the DCE shall return the ERROR result code; the DTE should discard
the frame.
After the status result code, the DCE shall accept new commands from the DTE.
The DCE shall obey the configured flow control from the DTE. If the DTE sends any
character to the DCE other than DC1 or DC3 while the DCE is in this mode, the DCE
shall enter command state and return the OK result code.
After sending the result code indicating that frame reception is complete, the DCE
shall continue to receive and buffer data in the selected mode. If the DTE issues
aFRH=<MOD> command, the DCE shall return another CONNECT result
code and continue with HDLC reception. If the DTE issues any command that
changes modulation, the DCE shall stop the receive process; any buffered data will be
discarded and the command will be obeyed.