User's Manual

Chapter 1 - Product Overview Landis+Gyr
10 98-1546 Rev AA UtiliNet SCADA Single Board Radio
Pins 6 and 7 (GND)
These pins are the ground connection for both power and communications. These two pins are tied
together on the device.
Pin 8 (LOW_RF_POWER)
The purpose for this pin is to reduce the RF output power level to assure operation during
development and OEM manufacturing process. A logic high on this pin leaves the device in its
normal mode of operation with full rated RF transmitter power. A logic low reduces the RF power
level to approximately 25 mW for use where high power is not required or maybe harmful. When the
USB cable is used to power the board, the pin is brought low. This pin is a digital input, driven at
TTL levels from 3.3 to 3.4 VDC.
This pin must be driven to a valid logic high or low as intermediate voltages will result in
indeterminate logic values and may damage the device.
Pin 9 (PWR_DN)
This pin is used to enable or disable the device. This pin is a digital input and must be driven to a
valid logic high or low, as intermediate voltages will result in indeterminate logic values and may
damage the device.
A logic high enables the linear regulator, thus powering the device.
A logic low disables the linear regulator and turns off the device.
Prior to turning off the device, all interface signals must be driven low and logic voltage removed.
This includes all Serial UART lines, digital and analog I/O lines.
When the device is turned off with this pin, total current consumption will be less than 2 µA.
Pin 12 (TPP RX) and Pin 13 (TPP TX)
These pins are used to interface with the device's Transparent Port. These pins are driven at TTL
levels from 3.3 to 3.4 VDC.
Baud rates on this port default to 9600 bps, but using RadioShop are configurable up to 38,400 bps.
To reduce chances of electrical damage, a 10Kohm series resistor is placed in-series with the pin
which limits the drive current capability of this pin.
Stray physical capacitance on this circuit should be kept below 250[pF].
When the board is not in use, voltage should not be applied to any interface as this may damage
the device as destructive latch-up can result.
These pins are NOT direct connect to an RS-232 interface on a computer and where such a
connection is necessary, the developer must purchase a TTL to RS-232 3.3 VDC converter which
is powered external and NOT via the pins or the RS-232 connection on the computer.