Fluke 45 user manual 7 6 5 4 3 2 1, Event Status and Event Status Enable Registers

45

Users Manual

Event Status and Event Status Enable Registers

The Event Status Register (ESR) assigns specified events to specific bits (see Figure 5-4 and Table 5-6). When a bit in the ESR is set (i.e., 1), the event that corresponds to that bit has occurred since the register was last read or cleared. For example, if bit 3 (DDE) is set to 1, a device-dependent error has occurred.

The Event Status Enable Register (ESE) is a mask register that allows the host to enable or disable (mask) each bit in the ESR. When a bit in the ESE is 1, the corresponding bit in the ESR is enabled. When any enabled bit in the ESR changes from O to 1, the ESB bit in the Status Byte Register also goes to 1. When the ESR is read (using the *ESR? com- mand) or cleared (using the *CLS command), the ESB bit in the Status Byte Register returns to 0.

Logical OR

Power On User Request Command Error Execution Error Device Dependent Error Query Error Request Control Operation Complete

7 6 5 4 3 2 1 0

&

&

&

& & &

& &

7 6 5 4 3 2 1 0

Standard

Event Status Register

*ESR?

Standard

Event Status Enable

Register

*ESE *ESE?

Summary Message

Event Summary Bit (ESB)

(Bit 5 of Status Byte Register)

aam22f.eps

Figure 5-4. Event Status and Event Status Enable Registers

Figure 5-4 reprinted from ANSI/IEEE Std 488.2-1987. Copyright 1988. By the Institute of Electrical and Electronics Engineers, Inc. By

permission of the IEEE Standards Department.

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