The Wi.M900T module is a microcontroller-less transmit-only
version of our popular Wi.232DTS module. It offers the same
excellent RF performance, yet allows the design engineer
to control the radio at the physical level using any microcontroller.
It is perfect for cost sensitive applications that only
require one way data transmission, such as bubble-up automated
meter reading.
The module is footprint compatible with the entire Wi.
(pronounced Y-DOT) module family, which includes the WiM900T,
WiM900X, Wi232DTS, and our soon to be announced Wi232FHSS-25.
This gives the designer a level of flexibility not offered
by any other solution from any other embedded wireless company.
The Wi.M900T is based on the XEMICS XE1203F transceiver
RFIC. After evaluating all of the wireless ICs available,
we chose the XE1203F as the heart of our Wi. series of modules
because it has by far the best performance and stability
of all chips available today.
The Wi.M900T is an excellent alternative to the DP1203
module offered by XEMICS, having several advantages over
this and other modules from other chip manufacturers. First,
the Wi.M900T is a member of a very flexible family of products
that are all footprint compatible. So if the designer starts
out with the Wi.M900T and later decides that using the Wi.232DTS
module is a better solution, it is as easy as dropping in
the new module. Second, our modules are all factory calibrated
and the calibration constants are stored in NV memory on
the module. By using these constants, the designer can calibrate
the module in software, eliminating the need for RF testing
in production
The module supports two modes of operation: wide-band
and narrow-band. In wide-band mode, the channel width is
600kHz and in narrow-band mode the channel width is 200kHz.The
module is configured via a simple SPI style serial interface.
Data is transmitted and received using a separate digital
serial interface that includes pre-amble and start-of-packet
detection.
Maximum transmit power is +15dBm. The transmitter draws
53mA typical at +15dBm.
868 and 915MHz versions are available.
A typical circuit consists of a low-cost microcontroller,
a power source, a Wi.M900T module, and an antenna.
