Setting the Digitizer Configuration

The digitizer configuration covered in this section includes:

∙setting the arm sources

∙setting the arm count

∙setting the arm delay

∙setting the reference source

∙setting the trigger source

∙sending arm immediate

∙sending trigger immediate

∙aborting measurements

Note

Setting the Arm Sources

The trigger count (pre-arm and post-arm reading counts) and the sample rate are set when the timebase processor is initialized. See "Initializing the Timebase Processor" in the section "Re-initiating the Digitizer" for more information.

The registers used to set the arm sources are listed below.

∙Arm Source register

base + 4916

∙Arm Control register

base + 4B16 (used when changing arm source while initiated)

Procedure The arm source can be set/changed when the digitizer is in the idle state or while it is initiated.

1.Setting/changing the arm source in the idle state:

A.Write the decimal equivalent bit pattern to the arm source register (base + 4916).

2.Setting/changing the arm source while initiated:

A.Suspend the arm trigger by setting bit 2 of the arm control register (base + 4B16) to ’1’ . Retain the settings of the other register bits.

B.Write the decimal equivalent bit pattern for the desired arm source to the arm source register (base + 4916).

C.Enable the arm trigger by setting bit 2 of the arm control register (base + 4B16) to ’0’ . Retain the settings of the other register bits.

Appendix C

Register Programming 373

Page 373
Image 373
HP E1429A manual Setting the Digitizer Configuration, Setting the Arm Sources