Measurement Computing TempScan/1100 - Manual (Page 109)

TempScan / MultiScan User's Manual 889897 System Operation 5-19
Theory of Operation
Each register is part of a hierarchy of status-reporting and mask registers where operations on higher
registers will affect the contents of lower registers in the chain. This hierarchical approach provides various
levels of status reporting. The lowest levels give general event status information while the higher levels
give more details of the particular events. In the same way that the setting of events or conditions affects
the lower-level registers in the chain, the clearing of events or conditions in the higher-level registers also
clears those affected conditions in the lower-level registers.
Status-Reporting Registers
The following four registers cover a wide range of internal error and event conditions. Each of these
registers covers a particular aspect of event reporting responsibility. These registers are briefly defined as
follows:
• Calibration Status Register (CSR): Read/Clear-Only, via the following User Status (
U
) command –
Query and clear the Calibration Status Register (
U2
). Indicates any error conditions during
TempScan/1100 or MultiScan/1200 calibration.
• Error Source Register (ESC): Read/Clear-Only, via the Query Error Status (
E?
) command. Indicates
any general error conditions with the TempScan/1100 or MultiScan/1200 unit.
• Event Status Register (ESR): Read/Clear-Only, via the following User Status (
U
) command – Query
and clear the Event Status Register (
U0
). Indicates special events that have occurred in the
TempScan/1100 or MultiScan/1200 unit.
• Status Byte Register (STB): Read-Only, via the Serial Poll (
SPOLL
) command (IEEE 488 only) or the
following User Status (
U
) command – Query the Status Byte Register (
U1
) (IEEE 488 or serial).
Indicates critical operation events with the TempScan/1100 or MultiScan/1200 unit.
Mask Registers
In addition, the following two mask registers are used to configure the status and event reporting registers.
These mask registers are briefly defined as follows:
• Event Status Enable Register (ESE): Read/Write/Clear, via the following Set Event Mask (
N
)
commands –
N?
,
Nmask
, and
N0
, respectively. A mask for the Event Status Register (
ESR
).
• Service Request Enable Register (SRE): Read/Write/Clear, via the following Set SRQ Mask (
M
)
commands –
M?
,
Mmask
, and
M0
, respectively. A mask for the Status Byte Register (
STB
).
Status-Reporting Registers
Calibration Status Register (CSR)
The Calibration Status Register (
CSR
) is a Read/Clear-Only register in that it may only be read and cleared
by the controller, via the following User Status (
U
) command – Query and clear the Calibration Status
Register (
U2
). The read operation is a destructive read since it clears the register as it is read. This register
can only be written to by internal TempScan/1100 or MultiScan/1200 operations.