EVM-915-DTS-BZS Linx Technologies, EVM-915-DTS-BZS Datasheet - Page 8

• Manufacturer Part Number: EVM-915-DTS-BZS
• Description: RF Development Tools 915 MHz Wireless Module DTS Brazil
• Manufacturer: Linx Technologies
• Type: Wi-Fir

Specifications of EVM-915-DTS-BZS

• Rohs: yes
• Product: Evaluation Modules
• Tool Is For Evaluation Of: Wi.232DTSB-R
• Frequency: 915 MHz
• Operating Supply Voltage: 3 V to 3.6 V
• Interface Type: UART
• Factory Pack Quantity: 1

for applications that are replacing legacy RS-485 networks. In peer-to-
peer mode, any module can hear any other module. In both modes, group
integrity is enforced.
When a module transmits a packet, all other modules on the same channel
will receive the packet, check the packet for errors, and determine whether
the received group ID matches the local group ID. If the packet is error
free and the group IDs match, the module will decrypt the data if neces-
sary, and send the error free data to its host UART for processing. The
modules only implement the ISO reference network stack up to the MAC
layer, so they are transparent to link layer addressing schemes. Therefore,
the modules can work with any link-layer and higher protocols in existence
today.
Certain features of the module are controlled through programmable regis-
ters. Registers are accessed by bringing CMD low. When CMD is low, all
data transfers from the host UART are considered to be register access
commands. When CMD is high, all data transfers from the host UART
are considered to be raw data that needs to be transparently transmitted
across the wireless link. The module maintains two copies of each register:
one in flash and one in RAM. On reset, the module loads the RAM registers
from the values in the flash registers. The module is operated out of the
RAM registers. Applications that need to change parameters of the module
often would simply modify the RAM registers. Putting default settings in
the flash registers ensures the module always comes up in a preconfigured
state, which is useful for applications that do not have external
microcontrollers, such as RS-232 adapters.
The UART interface is capable of operating in full duplex at baud rates from
2.4 to 115.2kbps.
The module has ten power modes: High LP, Mid-High LP, Mid-Low LP,
Low DTS, High DTS, Mid-High DTS, Mid-Low DTS, Low LP, Standby, and
Sleep.
The DTS Series is the first module in the world to take advantage of the
DTS digital spread spectrum provision in FCC part 15 rules. Under this
provision, transmitters can operate at a higher output power if the
transmission bandwidth is at least 500kHz. Through an encoding technique
we call DirectSPREAD™, the outgoing RF data is encoded with symbols
selected to ensure its average duty cycle is 50%. This allows the
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module to be able to operate at +11dBm and meet the requirements of
this provision.
In DTS mode, the module’s channel bandwidth is set to 600kHz and the
transmit power is set to one of four selectable levels. In this mode, the
module can operate on 32 channels and support a maximum effective RF
data rate of 100kbps. The receiver sensitivity at the max data rate is
−100dBm typical, yielding a link budget of 111dB. This mode is an
excellent alternative to Frequency Hopping Spread Spectrum. It has no
synchronization requirements, allowing it to operate in a duty-cycle mode
for extended battery life.
In low-power (LP) mode, the module’s channel bandwidth is set to 200kHz
and the transmit power is set to one of four selectable levels. In this mode,
the module can operate on 84 channels and support a maximum data rate
of 19.2kbps. The receiver sensitivity at the maximum data rate is –105dBm
typical, yielding a link budget of 102dB. This mode reduces transmit
current consumption, allowing use with batteries that cannot supply the
pulse currents required for DTS mode. The range in this mode will be a little
more than half of the range in DTS mode. Power settings other than low
are available in LP mode, but should only be used when the antenna circuit
is lossy.
If the current draw in sleep mode is too high for a particular application, the
designer can switch power to the module through a FET to “turn-off” the
module when it is not needed. If this technique is used, the volatile registers
will reset to the values in their non-volatile mirrors, so any changes from the
default will have to be reloaded.
The DTS Series is a very flexible module because of all of the configurable
parameters it supports. However, modules that are not configured in the
same way will not be able to communicate reliably, causing poor
performance or outright failure of the wireless link. All modules in a
network must have the same mode configuration to ensure
interoperability.
Every module has read-only internal registers that contain factory
programmed information that includes calibration data and a 48-bit
Note:
from other modules. Any data sent to the module while it is in sleep
mode will be lost.
When in sleep mode, the module will not be able to receive data
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