ETAS ES1336.1, Руководство пользователя

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Hardware 13
2.2 Synchronization Signals
The ES1336.1 Angle Synchronous Measurement Board can obtain current
angle information from the ES1335.1 Arbitrary Signal Generator Board via the
VME backplane.
This crankshaft angle clock signal consists of three parts (see Fig. 2-3):
• The synchronization signal at 0 °CA
• The actual clock signal
• The signal for the direction of rotation (DOR)
A “high” level of the DOR signal means “rotation with an increasing crank-
shaft angle”; a “low” level means “rotation with a decreasing crankshaft
angle”.
The following figure shows the course of the three signals during a camshaft
rotation.
Fig. 2-3 The Three Components of the Crankshaft Angle Clock Signal
The ES1336.1 Angle Synchronous Measurement Board can also be used as
master, i.e. it issues the angle clock signal on the VME backplane. The defini-
tion of whether the particular ES1336.1 works as an angle clock master or
slave is made in LABCAR-RTC (RTIO).
2.3 Angle Windows
For measurements in speed-synchronous mode, an angle window for measur-
ing is always determined by the RTIO parameters “CS Angle Lower Limit” and
“CS Angle Upper Limit”.
Three angle windows can be defined per hardware channel – the maximum
size of an angle window is 720 °CA.
V
Low
High
Synchronization
α
0 °CA
720 °CA
V
Low
High
V
Low
High
Clock
Direction of Rotation