Dt9837A, Dt9837B, And Dt9837C Register-Level Programming; Writing To The General Control Register 4 - Data Translation DT9837A User Manual

Appendix C
DT9837A, DT9837B, and DT9837C Register-Level
Programming
If you need to change the settings of the Open Layers Control Panel for the DT9837A,
DT9837B, or DT9837C programmatically, you can use the Data Acq SDK function
olDiagWriteReg to write to the following registers of the DT9837A, DT9837B, or DT9837C
module:
• General Control Register 4 – Write to this memory location to change the tachometer and
• EEPROM – Write to this memory location to change the coupling, current source, and
The following subsections describe writing to these memory locations in more detail.

Writing to the General Control Register 4

The following example shows how to update the bits of General Control Register 4 on the
DT9837A and DT9837B modules using the value specified in the RegValueToWrite variable:
#define LOCAL_BUS_BASE 0x400000
#define GENERAL_CNTRL_REG4 (LOCAL_BUS_BASE | 0x8)
olDiagWriteReg (m_hDev, GENERAL_CONTROL_REG4,RegValueToWrite,2);
General Control Register 4 (ControlReg4) Offset: 0x8
Note: The contents of the registers are reset once the application exits.
Table 37
modules that relate to the tachometer and gate settings in the Open Layers Control Panel,
described on
Bits Type
[15:14] RW
[13:12] RW
140
gate settings. The DT9837C module does not support this register.
high power mode settings.
describes the bits of General Control Register 4 on the DT9837A and DT9837B,
page 36.
Table 37: DT9837A and DT9837B General Control Register 4
Name
Tach Counter 1 Start Select
Gate Counter 2 Start Select
Description
Select the starting edge for the Tach Counter 1
measurement function:
00 – A/D Ready Falling Edge
01 – Reserved
10 – Tach Input Falling Edge
11 – Tach Input Rising Edge
Select the starting edge for the Gate Counter 2
measurement function:
00 – A/D Ready Falling Edge
01 – Reserved
10 – Gate Falling Edge
11 – Gate Rising Edge