Quatech 802.11B/G - Manual (Page 26)

Quatech, Inc. Airborne Enterprise Module Databook
26 7/15/2010 100-8080-120
Command
(Hex)
Name Description
0x40 TXDATA The TXDATA command is used to send data to the module to
be interpreted as commands if the module is in CLI mode, or to
be transmitted on the wireless link if the module has an active
data connection established.
The host may send at most the number of bytes indicated by the
TX Buffer Available field in the RX Message Header. The actual
number of bytes sent by the host is determined by the 16 bit
value in PARM2. The value in PARM2 is little-endian (LSB first)
and must be less than or equal to the number in the TX Buffer
Available field. Any bytes sent in excess of this number will be
ignored.
PARM1 is unused for this command and should be set to zero.
For example, to send the auth dpac dpac command, use the
SPI message 0x40 0x00 0x0F 0x00 0x61 0x75 0x74 0x68 0x20
0x64 0x70 0x61 0x63 0x20 0x64 0x70 0x61 0x63 0x0D. That
is, SPI command 0x40, PARM1 is 0x00, PARM2 is 0x000F,
followed by the text for auth dpac dpac.
0x80 RXDATA The RXDATA command is used to receive data from the
module. In CLI mode, this data will be the local echoing of the
commands issued to the module, as well as the command
responses generated by the module. If the module has an
active data connection established, this data will be the data
received on the wireless link.
The host may receive at most the number of bytes indicated by
the RX Data Available field in the RX Message Header. The
actual number of bytes received by the host is determined by
the 16 bit value in PARM2. The value in PARM2 is little-endian
(LSB first) and must be less than or equal to the number in the
RX Data Available field. If additional clock cycles are sent to the
module beyond this number, meaningless data will be returned.
PARM1 is unused for this command and should be set to zero.
The TXDATA and RXDATA commands can be combined for full-duplex
operation. For example, a command byte of 0xC0 would be a TXDATA and
RXDATA command combined. The result of this command would be that the
module would accept data being shifted in as TX data, while at the same time,
RX data would be shifted out. In this case, the number of bytes transferred for
TXDATA must be equal to the number of bytes transferred for RXDATA. The
PARM2 parameter will indicate the number of bytes to be transferred for both the
TXDATA and RXDATA commands.