Technical data

7.3 Messages of the Power Supply Unit on Remote Control
7.3.1 Description of the Unit State
The current status of the unit’s operating conditions can be indicated via the EVENT
STATUS REGISTER and the STATUS BYTE REGISTER at any time.
7.3.1.1 ESR - EVENT STATUS REGISTER
The contents of the ESR register are saved in the output buffer and deleted by transmission of
the command *ESR? from the PC. The ESR register can also be set on Ø (except bit 7) by
switching on the unit, by transmitting the command *CLS or after activation of the interface
GPIB.
Contents of the ESR register: ESR xxx
Bit 7: (PON) Power On, operating readiness and activation of the interfaces are displayed
on 1.
6: (URQ) User Request, is not used, is always set on Ø.
5: (CME) Command Error, is set on 1 in the event of instruction errors.
4: (EXE) Execution Error, is set on 1 in the event of request errors and execution errors.
3: (DDE) Device Dependent Error, unit errors are displayed on 1.
2: (QYE) Query Error, is set on 1 at request errors.
1: (RQC) Request Control, is not used, is always set on Ø.
Ø: (OPC) Operation Complete, is set on 1 by transmission of the command *OPC.
Various states and settings of the unit can be checked. For this the contents of the ESR
register are called with the help of a mask (ESE - EVENT STATUS ENABLE REGISTER).
The single bits are compared and evaluated by the following logical equation:
ESB = (ESR7
∧ ESE7) ∨ (ESR6 ∧ ESE6) ∨ (ESR5 ∧ ESE5) ∨ (ESR4 ∧ ESE4) ∨
(ESR3 ∧ ESE3) ∨ (ESR2 ∧ ESE2) ∨ (ESR1 ∧ ESE1) ∨ (ESRØ ∧ ESEØ)
The result ESB (Event Summary Bit) is saved in the STB register.
The command *ESE xxx offers the possibility of initializing the ESE register with any mask.
The value xxx has to be within the range of Ø to 255.
The current contents xxx are in the output buffer after transmitting the command *ESE?.
The contents of the register can set on Ø (except bit 7) by switching on the unit, by
transmitting the command *CLS or after activating the interface GPIB.
7.3.1.2 STB - STATUS BYTE REGISTER
The contents of the STB register are saved in the output buffer by transmission of the
command *STB?. The STB register can be set on Ø by switching on the unit, by transmitting
of the command *CLS or after activating the interface GPIB.
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Operating Instructions PN 300
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