Usage Guidelines | Handling SRQ and the IEEE488.2 Status Structures |
What happens when power is turned on
The first element of the Power Module Status Structure we should look at is the Events Register.
The Events Register
The Events Register, together with its corresponding Events Enable Register generates the summary bit. Note that the Events Enable Register is common to all the Power Modules.
The Events Enable Register determines which of the Power Modules Events may cause an SRQ.
The content of the Events Register is cleared when read.
The Events Register, in turn, receives its data from the filtered status registers. The status registers’ data is filtered using the mask registers. The following paragraphs will describe the behavior of the status registers and their associated mask registers.
The Error Code
This register holds the last known error detected by the Power Module. The content of this register is cleared when read.
Whenever the Power Module detects a new error, the corresponding bit of the Event Register is set as well (a positive fixed mask).
The Faults Register
This register indicates the faults detected by the Power Module’s controller. This is a status register (showing the current state of the Power Module) but most of the faults are “sticky” – the fault condition remains true until a reset command is issued.
Any new fault detected by the Power Module’s controller will cause the corresponding bit of the Events Register to be set (a positive fixed mask). The exception to this rule is the Sense Warning condition, which is depicted in the Faults Register but is filtered the same way that warning events are (see bellow).
The Output Register
This status register depicts the current state of the Power Module’s output circuitry.
Any change in the Output status register will cause the corresponding bit of the Events Register to be set (no masking).
The Warnings Register
This status register indicates warning conditions. As it is a status register, it will indicate the current true state of the warnings.
Using the programmable mask registers (both positive and negative masks) the conditions that will cause the WRN bit of the Events Register to be set can be determined.
These mask registers are individual to each Power Module and enable a very flexible setup. A description of this feature is included in the Status Reporting chapter of the Programming Manual.
An IEEE488.2 defined command (*PSC) determines what will the XMP 2600 do with the event enable registers when turned on.
The *PSC command may enable the XMP 2600 to clear all the events enable registers and the SRQ Enable Register.
This feature ensures that the XMP 2600 wakes up with a known state. It also ensures that the XMP 2600 will not generate undesirable SRQ’s at power on.
XMP 2600 Programming Manual rev. 1.1 | 15 |
