The Questionable Signal Status Group

The Condition Register

The digitizer’s Questionable Signal status group monitors overload conditions, the frequency accuracy of the divide-by-n reference source, and error conditions in non-volatile calibration memory.

Overload conditions, divide-by-n frequency accuracy, and non-volatile calibration memory errors are monitored with the following bits in the Condition register. All other bits are unused.

15

14

13

 

12

 

11

10

9

8

7

6

 

5

 

4

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

unused

 

 

 

CAL

 

 

unused

 

 

TIME

 

VOLT

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

VOLTage: Bit 0 is set (1) if an amplifier overrange (single-ended or differential input) is detected during a measurement sequence. Otherwise, the bit remains cleared (0).

TIME: Bit 2 is set (1) when the divide-by-n reference source cannot generate a sample rate that is within 1% of the rate specified by TRIG:TIMer1 or TRIG:TIMer2. Otherwise, the bit remains cleared (0).

CALibration: Bit 8 is set (1) when an error is detected in non-volatile calibration memory.

Reading the Condition Register

The current state of bits 0, 2, and 8 can be determined by reading the

Condition register with the command:

STATus:QUEStionable:CONDition?

Bit 0 has a corresponding decimal value of 1, bit 2 has a decimal value of 4, and bit 8 has a decimal value of 256. Reading the Condition register does not affect the bit settings. The bits are cleared following a reset (*RST). Bit 8 CALibration will remain set, however; if the error condition persists.

The Transition Filter The Transition Filter specifies which type of bit transition in the Condition register will set corresponding bits in the Event register. Transition filter bits may be set for positive transitions ( 0 to 1), or negative transitions (1 to

0). The commands used to set the transitions are:

STATus:QUEStionable:NTRansition <unmask >

STATus:QUEStionable:PTRansition <unmask >

Chapter 3

Understanding the HP E1429 Digitizer 167

Page 167
Image 167
HP E1429A manual Questionable Signal Status Group, Reading the Condition Register