IP200 ETC [List of Unclassifed Manufacturers], IP200 Datasheet - Page 20

• Manufacturer Part Number: IP200
• Description: Interpolation Circuit for Incremental Measuring Systems
• Manufacturer: ETC [List of Unclassifed Manufacturers]

7
A signal edge event on pin TRG/GFE stores the current measurement result (counter value) in one of the
two-level deep trigger hold register. The active trigger edge is configured by the configuration bit TRGSLP
(register CFG1).
A read access to the register MVAL returns the “oldest” value of the trigger hold register. If the trigger register
contains no active value, the current counter value returns in result of the read access. It is possible to save
the results of two trigger events. While not both trigger register would be read out, all following trigger events
are ignored. The TRGOVL bit in register MVAL is set, if a trigger event occurs and both trigger hold register
contains valid data.
Every SPI read access to the register MVAL releases one trigger hold register. Only if trigger hold register 1
is empty (TR1=0), a new trigger processing is possible. If the parallel interface used solely as output port,
the pin CLRTRG must be operated to confirm the reading of one trigger event result.
A logic “1” in the FROZEN bit out of the register MVAL indicates the source of the read value as trigger result.
A logic “0” in this bit indicates the read access as normal read of the counter value. The actual state of the
trigger is coded in the bits TR(1:0)of the status register (STAT).

For applications which need fast response time related to trigger events and a high data rate on the serial
port as well , it could be better to read out only the 16 LSB of the MVAL register to check out if a trigger event
occurred.
TR(1:0) TRGOVL
D-09116 Chemnitz, Germany
00
01
10
11
10
11
Measurement Trigger
Zwickauer Straße 227
GEMAC
Gesellschaft für
Mikroe lektronikanwendung Chemnitz mbH
0
0
0
0
1
1
FROZEN
0
1
1
1
1
1
Phone:
Fax::
Internet:
Email:
Date: 20.04.04
MVAL contents
Current counter value
Trigger Hold Register 0 Storing to Trigger Hold Register 1
Trigger Hold Register 1 Storing disabled, TRGOVL will be set
Trigger Hold Register 0 Storing disabled, TRGOVL will be set
Trigger Hold Register 1 Storing disabled, TRGOVL is set
Trigger Hold Register 0 Storing disabled, TRGOVL is set
[phone] - 0
[phone]
www.gemac-chemnitz.de
[e-mail]
[e-mail]
Page 20 of 30
next Trigger Event
Storing to Trigger Hold Register 0
Title:
Data Sheet GC-IP200
Name of Document:
43500-DB-2-1-E-IP200.pdf