X09-009NSC Digi International/Maxstream, X09-009NSC Datasheet - Page 10

• Manufacturer Part Number: X09-009NSC
• Description: MOD RF 900MHZ 9600BPS W/RPSMA
• Manufacturer: Digi International/Maxstream

Specifications of X09-009NSC

• Frequency: 900MHz
• Data Rate - Maximum: 19.2kbps
• Modulation Or Protocol: FSK
• Power - Output: 100mW
• Sensitivity: -110dBm
• Voltage - Supply: 5V
• Current - Receiving: 50mA
• Current - Transmitting: 140mA
• Data Interface: PCB, Through Hole
• Antenna Connector: RP-SMA
• Operating Temperature: 0°C ~ 70°C
• Package / Case: Module
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Applications: -
• Memory Size: -

XStream™ OEM RF Module – Product Manual v5.x00 [2006.02.24]
2.1.2. Flow Control
DI (Data In) Buffer and Flow Control
DO (Data Out) Buffer and Flow Control
How to eliminate the need for flow control:
Two cases in which the DI Buffer may become full and possibly overflow:
Two cases in which the DO Buffer may become full and possibly overflow:
Figure 2‐03. Internal Data Flow Diagram (The five most commonly‐used pin signals shown.)
When serial data enters the XStream Module through the DI Pin (pin 4), then the data is stored in
the DI Buffer until it can be transmitted.
When the RB and RO parameter thresholds are satisfied (refer to Transmit Mode section [p11]
and command descriptions for more information), the module attempts to initialize an RF
connection. If the module is already receiving RF data, the serial data is stored in the DI Buffer.
The size of the DI Buffer can be determined by issuing the RZ (DI Buffer Size) Command. If the
DI buffer becomes full, hardware or software flow control must be implemented in order to
prevent overflow (loss of data between the host and XStream Module).
1.
2.
1.
2.
Hardware Flow Control (
the module de-asserts (high)
(Flow Control Threshold) and CS (DO2 Configuration) Commands].
Buffer has 34 bytes of memory available.
Software Flow Control (XON). XON/XOFF software flow control can be enabled using the FL
(Software Flow Control) Command. This option only works with ASCII data.
When RF data is received, the data enters the DO buffer and is then sent out the serial port to a
host device. Once the DO Buffer reaches capacity, any additional incoming RF data is lost. The
size of the DO Buffer can be determined by issuing the RZ (DI Buffer Size) Command, then
multiplying the result by 1.5.
1.
2.
Hardware Flow Control (
be sent out the DO Buffer as long as
Software Flow Control (XOFF). XON/XOFF software flow control can be enabled using the FL
(Software Flow Control) Command. This option only works with ASCII data.
© 2006 MaxStream, Inc. Confidential and Proprietary
Send messages that are smaller than the DI buffer size. The size of the DI buffer varies
according to the packet size (PK parameter) and the parity setting (NB parameter) used.
Interface at a lower baud rate (BD parameter) than the fixed RF data rate.
If the serial interface data rate is set higher than the RF data rate of the module, the module
will receive data from the host faster than it can transmit the data over-the-air.
If the module is receiving a continuous stream of RF data or monitoring data on a network,
any serial data that arrives on the DI pin is placed in the DI Buffer. The data in the DI buffer
will be transmitted over-the-air when the module no longer detects RF data in the network.
If the RF data rate is set higher than the interface data rate of the module, the module will
receive data from the transmitting module faster than it can send the data to the host.
If the host does not allow the module to transmit data out from the DO buffer because of
being held off by hardware or software flow control.
). When the DI buffer is 17 bytes away from being full; by default,
). If
to signal to the host device to stop sending data [refer to FT
is enabled for flow control (RT Parameter = 2), data will not
(pin 5) is de-asserted.
is re-asserted after the DI
10