The Arm and Trigger Configuration Registers

The following registers are used to set the digitizer’s arm and trigger parameters.

The Abort and Arm Immediate Register

base + 4116

The function of the Abort and Arm Immediate register depends on whether you are writing to the register, or reading the register. Its useage is defined as follows

Address

base + 4116

7

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

register write: measurements aborted

register read: arm immediate

Writing any 8-bit value to this register aborts the current measurements.

Reading this register arms the digitizer if the digitizer is initiated (wait-for-arm state). Once armed, the digitizer moves to the wait-for-trigger state.

The Arm Status Register

 

 

 

 

 

 

base + 4316

 

The arm status register monitors states and conditions associated with the

 

digitizer’s arming hardware. The register bits are defined below.

 

 

 

 

 

 

 

 

 

 

 

 

Address

 

7

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

base + 4316

 

128

64

32

16

8

4

2

1

 

 

 

 

 

 

 

 

 

 

 

 

Purpose

 

Pre-

Stage2Q

No arm

Last

Begin

Delayed

Initiated

Initialized

 

 

 

delay

 

 

TRG*

samp

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Pre-delay:Bit 7 is set to ’1’ when an arm signal is received, but the arm delay (as set by the arm delay register) must elapse before the digitizer is armed. When arm immediate is used with the dual rate sampling mode (bit

5:base + 4B16), bit 7 is set to ’1’, one reference period before the digitizer is actually armed.

Stage2Q: Bit 6 is set to ’1’ when an arm signal other than an arm immediate is received.

No arm: Bit 5 is set to ’1’ while the digitizer is taking pre-arm readings. The bit is set to ’0’ when the pre-arm count is reached. This bit is checked before an arm immediate is sent (a write to base + 4116).

Appendix C

Register Programming 353

Page 353
Image 353
HP E1429A manual Arm and Trigger Configuration Registers, Abort and Arm Immediate Register, Arm Status Register, Base +