System 3
3-39
RX7 Stimulator Base Station
However, the need may arise to run a circuit at a higher sampling rate while still
acquiring data via a fiber optic port. The first two fiber optic ports on an RX device
can oversample the digitized signals that have already been sampled up to 4X or
~100 kHz. This will allow an RX7 to run a DSP chain at ~50 kHz or ~100 kHz,
and still sample data acquired through an optically connected preamplifier that
digitized the incoming data stream at its maximum rate of ~25 kHz.
Oversampling is performed on the base station. The signals being acquired will still
be sampled at ~25 kHz on the preamplifier. This means that, even with
oversampling, signals acquired by an optically connected preamplifier are still governed
by the bandwidth and frequency response of the preamplifier.
When acquiring up to 16 channels of data on the first fiber optic input port of the
RX7, the signals will be oversampled 4X to ~100 kHz. If the RX7 is equipped with
a second fiber optic input port and data is being acquired on both ports, the signals
on second port will be oversampled 2X to ~50 kHz.
Amp
Status
and
Clip
Warning
Lights
Amp lights are located to the right of each fiber optic port. These lights are used to
indicate the power status or provide a clip warning for the connected amplifiers.
When an amplifier is not connected the Amp light will flash in a slow steady pattern.
The light is lit when the amplifier is connected and begins to flash quickly when the
voltage on the battery for the corresponding amplifier is low. When any channel on
the connected amplifier produces a voltage approaching the maximum input of the
amplifier, the corresponding light will flash rapidly to warn that clipping may occur if
the signal exceeds the maximum input voltage. See the corresponding preamplifier
section for more information on input range and clip warnings.
Important!
The Li-ion batteries voltage decreases rapidly once the battery low light is on. Data
acquisition will suffer if the battery is not charged soon after the light goes on.
Amplifier
Status
Patterns
Note:
If the amplifier appears to be connected and the amplifier status light is flashing
slowly, check to ensure that the device is connected properly.
Bits
Lights
The RX7’s eight Bits lights are user configurable. By default the Bits lights indicate
the logic level (light when high) for the eight bit-addressable digital I/O lines. The
Bits lights can also be configured to provide information about amplifier status or act
as logic level lights for any of the other four bytes of digital I/O.
Light Pattern
Amplifier Status
Solid
Connected
Very slow flash (~1 every two seconds)
Not connected
Slow flash (~1 per second)
Connected and charging
Rapid flash
Battery low
Very rapid flash
Clip Warning