Omega Engineering OMB-CHARTSCAN 1400, User Manual

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Appendix C Registers, Data Formats, & Queries
ChartScan User’s Manual C-15
Status Byte Register
The acquisition device sets the Message Available bit (MAV) in the Status Byte Register to determine if data
can be read by the controller. This is the only status reporting register which requires RS-232 interface users to
use a different read command than IEEE 488 interface users.
The status byte register contains the following active bits:
Bit Location Value Description
DIO1 (LSBit)
1 Alarm
DIO2
2 Trigger Detected
DIO3 4 Ready
DIO4
8 Scan Available
DIO5
16 Message Available
DIO6 32 Event Status Register Bit (ESB)
DIO7
64 Service Request Bit
DIO8 (MSBit)
128 Buffer Overrun
All bits in the serial poll status byte register are cleared by either a
*R
command, that returns ChartScan to its
power-up default conditions, or a read of the serial poll status byte register via the Status command
U1
. The
ESB in the Serial Poll Status Register is also cleared by these operations. The Command Error, Execution Error
and Device Dependent Error are also cleared with an Error Query (
E?
) command.