User Manual

Chapter 1 - Product Overview Landis+Gyr
10 98-1138 Rev AD Gridstream SCADA/DA S4SBR
A logic low (pin connected to ground) reduces the RF output power level to approximately 100 mW
for use in environments where high RF output power is not required or only low input power is
available to the device. When the USB cable is used to power the board, the pin is automatically
brought low. This pin is a digital input, driven internally at TTL supply level.
This pin must be left not connected or pulled low to ground as intermediate voltages will result in
indeterminate conditions and may damage the device.
Pin 9 (PWR_DN)
This pin is used to enable or disable the Gridstream S4SBR. It is a digital input and must be driven to
a valid logic high (5.0 VDC) or low (GND), since intermediate voltages will result in indeterminate
logic values and may damage the device.
 NOTE: When the Pin 9 power-off command is asserted on super-capacitor units, the unit will remain
operational for a few minutes as the super-capacitor voltage bleeds off. Once Pin 9 power-off
command is asserted on units without the super-capacitor, the units will turn off immediately.
• A logic high (5VDC) provides power to the device.
• A logic low (GND) turns off the device.
Prior to turning off the device, all interface signals must be driven low and logic voltage removed.
This includes all TTL logic lines, digital and analog I/O lines.
When the device is turned off with this pin, total current consumption will be less than 100µA.
 NOTE: When the board is not in use, voltage should not be applied to any interface. Applied voltage
may damage the device as destructive latch-up may occur.
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
supply level.
Baud rates on this port default to 9,600 bps but, using RadioShop, are configurable from 300 bps to
115,200 bps.
To reduce chances of electrical damage, a 1Kohm 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].
 NOTE: These pins should NOT be directly connected to an RS-232 interface on a computer. Where
such a connection is necessary, the developer must purchase a TTL to RS-232 VDC converter
which is powered external and NOT via the pins or the RS-232 connection on the computer.
draft 29 Jan 2013