XStream
‐
PKG
‐
T™
Telephone
RF
Modem
–
Product
Manual
v5.x00
[2006.02.24]
FT (Flow Control Threshold) Command
AT Command: ATFT
Binary Command: 0x24 (36 decimal)
Parameter Range: 0 – ( Receiving module DO
buffer size minus 0x11 bytes)
Default Parameter Value: Receiving module
DO buffer size minus 0x11
Number of bytes returned: 2
Minimum Firmware Version Required: 4.27B
<Serial Interfacing> Set/Read the flow control
threshold. When FT bytes have accumulated in
the DI buffer,
is de-asserted or the XOFF
software flow control character is transmitted.
GD (Receive Good Count) Command
<Diagnostic> Set/Read the count of good
received RF packets. Parameter value is reset to
0 after every reset and is not non-volatile (Value
does not persist in the module’s memory after a
power-up sequence). Once the “Receive Good
Count” reaches its maximum value (up to
0xFFFF), it remains at its maximum count value
until the maximum count value is manually changed or the module is reset.
AT Command: ATGD
Binary Command: 0x10 (16 decimal)
Parameter Range: 0 – 0xFFFF
Default Parameter Value: 0
Number of bytes returned: 2
Related Commands: ER (Receive Error Count)
HP (Hopping Channel) Command
AT Command: ATHP
Binary Command: 0x11 (17 decimal)
Parameter Range: 0 – 6
Default Parameter Value: 0
Number of bytes returned: 1
Related Commands: DT (Destination Address),
ID (Modem VID), MK (Address Mask)
<Networking> Set/Read the channel on which a
modem communicates. A channel is one of three
layers of addressing available to the radio
modem. In order for modules to communicate
with each other, the modules must have the
same channel number since each channel uses a
different hopping sequence. Different channels
can be used to prevent modules in one network
from listening to transmissions of another.
HT (Time before Wake-up Initializer) Command
AT Command: ATHT
Binary Command: 0x03 (3 decimal)
<Sleep (Low Power)> Set time of inactivity (no
serial or RF data is sent or received) before a
wake-up initializer is sent. This allows a base
station to track the awake-status of remotes.
Parameter Range: 0 – 0xFFFF
If any radio modems within range are running in
a “Cyclic Sleep” setting, a wake-up initializer is
used by the transmitting module to notify
sleeping modules that data is coming and they
should wake from cyclic sleep [refer to the LH
(“Wake-up Initializer Timer”) Command]. When
a receiving module in Cyclic Sleep wakes, it must detect the wake-up initializer in order to remain
awake and receive data. The value of HT parameter tells the transmitter, “After a period of
inactivity (no transmitting or receiving) lasting HT time, send a wake-up initializer”.
[x
100
milliseconds]
Default Parameter Value: 0xFFFF (means that
wake-up initializer will not be sent)
Number of bytes returned: 2
Related Commands: LH (Wake-up Initializer
Timer), SM (Sleep Mode), ST (Time before Sleep)
NOTE: HT of the base radio should be set shorter than ST of remote radios.
From the receiving module perspective: After HT time elapses and the inactivity timeout [ST
Command] is met, the receiver goes into cyclic sleep. In cyclic sleep, the receiver wakes once per
sleep interval to check for a wake-up initializer. When a wake-up initializer is detected, the
module will stay awake to receive data. The wake-up initializer must be longer than the cyclic
sleep interval to ensure that sleeping modules detect incoming data. When HT time elapses, the
transmitter then knows that it needs to send a wake-up initializer for all receivers to be able to
remain awake and receive the next transmission. Matching HT to the time specified by ST on the
receiving module guarantees that all receivers will detect the next transmission.
©
2006
MaxStream,
Inc.,
Confidential
and
Proprietary
51
