KSI/Odetics TPRO/S IRIG Interface


Address: 127.127.12.u
Reference ID: IRIG
TPRO Device: /dev/tprou
Requires: KSI/Odetics device driver, /usr/include/sys/tpro.h header file


This driver supports the KSI/Odetics TPRO and TPRO-SAT IRIG-B Decoder, which is a module connected directly to the SBus of a Sun workstation. The module works with the IRIG-B signal generated by several radio clocks, including those made by Arbiter, Austron, Odetics, Spectracom and TrueTime, among others, although it is generally an add- on option. In the case of the TPRO-SAT, the module is an integral part of a GPS receiver, which serves as the primary timing source.

Using the TPRO interface as a NTP reference clock provides precision time only to ntpd and its clients. With suitable kernel modifications, it is possible to use the TPRO as the CPU system clock, avoiding errors introduced by the CPU clock oscillator wander. See the A Kernel Model for Precision Timekeeping page for further details.

Monitor Data

The driver writes each timecode as received to the clockstats file.

Fudge Factors

time1 time
Specifies the time offset calibration factor, in seconds and fraction, with default 0.0. For a calibrated Sun IPC, the correct value is about .00037.

time2 time
Not used by this driver.

stratum number
Specifies the driver stratum, in decimal from 0 to 15, with default 0.

refid string
Specifies the driver reference identifier, an ASCII string from one to four characters, with default IRIG.

flag1 0 | 1
Not used by this driver.

flag2 0 | 1
Not used by this driver.

flag3 0 | 1
Not used by this driver.

flag4 0 | 1
Not used by this driver.

Additional Information

Reference Clock Drivers

David L. Mills (mills@udel.edu)