### KSI/Odetics TPRO/S IRIG Interface

Author: David L. Mills (mills@udel.edu)
Last update: 03-Sep-2010 20:44 UTC

#### Synopsis

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

#### Description

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.

#### Fudge Factors

`time1 time`
  Specifies the time offset calibration factor, in seconds and fraction, with default 0.0.
`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