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Configuration
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© 2012 Patapsco Designs Ltd
7.2. Clock Sources
The correct configuration of clock sources is essential to any DataBand EV system.
DataBand EV has an extremely accurate onboard oscillator. It is worth considering using DataBand EV's onboard oscillator to
generate clock for a system instead of using the oscillator of a connected device. The standard oscillator is accurate to 150 PPB
(parts per billion) within a temperature range of -20 to +70°C, and has a Drift value as low as 40 PPB over 24 hours.
Even more accurate oscillators can be fitted to DataBand EV for applications where clocking is especially critical, or outside factors
such as temperature change are present. Please
Select Internal or E 1/T1 clocking for DataBand EV.
7.3. Port Settings
Port Type
E 1 refers to the 2Mb TDM protocol used in most of the world which supports up to 32 timeslots (2.048Mbps). Timeslot 0 is used for
framing, leaving 31 timeslots available for call traffic.
T1 is the TDM protocol used in North America and Japan. This protocol supports 24 timeslots, all of which can be used for data.
Note: Channels are only connected between ports when a connection is detected on the related E1/T1 ports.
T1 Settings
DataBand EV supports two types of T1 Framing standard and Line Code. These cover the requirements most T1 equipment. Please
contact Patapsco with any additional requirements. Select the Framing and Line Code using the radio buttons.
Line Code
B8ZS - Bipolar with 8 Zeros Substitution - Point-to-point T-carrier line coding.
AMI - Alternate Mark Inversion - Basic bipolar encoding.
F raming
E SF - Extended Superframe - Sometimes referred to as D5, this is the successor to Superframe and includes CRC checking.
D4 - Basic TDM framing standard.
N*64
DataBand EV will automatically map all channels from the E1/T1 interface to the Serial interface unless the N *64 option is set.
Enabling N *64 opens a window showing the available E1/T1 channels. Use the tickboxes to add or remove channels from the
connection.
CRC4