Overview

Time resolution is a key point in selecting the time stamped event sources.

Time and time stamp resolution are to be understood as follows:

Internal module time resolution:

Absolute time resolution depending on the module internal clock time management.
Time stamp resolution between 2 events in the same module:

Depends on the module internal Input (and Output) event detection cycle.
Time stamp resolution between 2 events on different source modules of the same family (BMX ERT 1604 T or BM• CRA 312 10):

Time resolution between 2 source modules depends on the time source (external clock) tolerance, each module internal time resolution, and the network transmission delay for modules synchronized through NTP.
Time stamp resolution between 2 events on different source modules of a different family (BMX ERT 1604 T and BM• CRA 312 10 or BME P58 ••••):

Same constraints as with 2 source modules of the same family, except that the time stamp resolution will be the one of the less accurate module.

Time and Time Stamp Resolution

Value

System Events Source Modules

Value

Comment

Internal time resolution

BME P58 ••••

1 ms

Internal clock resolution

BMX ERT 1604 T

1 ms

Internal clock resolution

BM• CRA 312 10

Internal clock resolution

Time stamp resolution between 2 events in the same module

BME P58 ••••

MAST task scan time

  

BMX ERT 1604 T

1 ms

  

BM• CRA 312 10

BM• CRA 312 10 scan time

(average value 3 ms)

Time stamp resolution depends on the module scan time.

Time stamp resolution between 2 events on different source modules

n x BMX ERT 1604 T (1.)

  • 2 ms with IRIG-B 004/5/6/7 time code (GPS)

  • 4 ms with DCF77 time code
NOTE: Time stamp resolution is given if each BMX ERT 1604 T module is supplied with the same time source.

n x BM• CRA 312 10 (1.)

10 ms

  

n x BMX ERT 1604 T

+ n x BM• CRA 312 10 (1.)

10 ms
NOTE: The worst time stamp resolution becomes the system time stamp resolution.

BME P58 ••••

+ n x BMX ERT 1604 T

+ n x BM• CRA 312 10 (1.)

Maximum of following values:

  • MAST task scan time

  • 10 ms
NOTE: The worst time stamp resolution becomes the system time stamp resolution.

1. n = many modules, maximum value depends on system architecture.