Omega Vehicle Security 1400 manual Using Status Reporting Registers, DI02

Appendix C Registers, Data Formats, & Queries

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.

Bit Location	Description	Set, Clear and Descriptive Information
DI01	Alarm	Set when the acquisition system has sensed a valid alarm condition. The alarm is cleared when
		the alarm condition no longer exists.
DI02	Trigger	Set when the acquisition system has detected the trigger condition and will be cleared when the
	Detected	acquisition is complete or the trigger has been reconfigured.
DI03	Ready	Set when the acquisition system is ready to process another command. It is cleared when the
		system is processing a command line. This bit should be examined with a serial poll prior to
		issuing a new command line. This allows any detected errors to be traced to the specific
		command line containing the error. If all the setup information for the operation of a specific
		acquisition system is included in one line, this bit also indicates when all processing is done and
		the X command is completed. This ensures that the acquisition system is done processing all
		state changes before initiating any further activity.
DI04	Scan	Set when at least 1 acquisition scan is available in the acquisition buffer to be read. Cleared
	Available	when there are no scans available in the buffer to be read.
DI05	Message	Set when the output queue is not empty. It is cleared when the output queue is empty. This bit
	Available	reflects whether any command responses are still in the output queue.

(MAV)

DI06	Event Status
	Register Bit
	(ESB)
DI07	Service
	Request Bit
	(SRQ)
DI08	Buffer
	Overrun

Reflects the logical OR of all the bits in the Event Status Register (ESR) ANDed with their equivalent enable bits in the Event Status Enable (ESE) register. If this bit is set, at least one bit in the ESR is set and has its corresponding enable bit in the ESE set. The status command U0 can be issued to read the ESR. See the following for more information on ESR and ESE.

Set when the acquisition system is requesting service. It is cleared when an SPOLL is performed.

Set if a buffer overrun occurs. It is cleared when the buffer becomes empty by either reading out the contents of the buffer or performing a Reset (*B) of the buffer.

Using Status Reporting Registers

As mentioned earlier the status reporting registers are organized in a hierarchical structure with the lower level registers containing more general information and the higher level registers containing more detailed information about particular events. In general, the lowest level register, the Status Byte Register (STB) contains information that may require more immediate action from the controller in that events contained in this register tend to be more time critical.

However, as mentioned earlier, other registers may access the STB via the ESB bit. This allows any condition within the status reporting register hierarchy to have access to the STB and therefore Serial Poll and Service Request functionality. The following is an example to show, in brief, how the status reporting register hierarchy works. Notice that the clearing of the higher level registers cleared the bits in the lower level registers that were associated with the root cause of the condition.

PRINT#1,"OUTPUT07;	N0	X	N16	X"	‘ Configure ESB in the STB to be set when a Device
					Dependent Error occurs.
PRINT#1,"OUTPUT07;	M0	X	M32	X"	‘ Configure SRQ when the ESB in the STB occurs.

A Device Dependent Error will now cause ChartScan to issue a Service Request (SRQ) to the controller. When the SRQ occurs, the controller may perform the following sequence to determine the exact cause of the Service Request.

PRINT#1,"OUTPUT07;E?X"	‘ Query the ESC to determine the cause of the error
PRINT#1,"ENTER07;	‘ Get the response
INPUT A$	‘ Screen shows E016.This is a calibration error
PRINT A$
PRINT#1,"OUTPUT07;U2X"	‘ Query the CSR to determine the cause of the ‘ calibration error
PRINT#1,"ENTER07;	‘ Get the response
INPUT A$	‘ Screen shows E002. This is a calibration Gain error
PRINT#1,"OUTPUT07;U0X"	‘ Now query the ESR (reading ESC should have cleared it)
PRINT#1,"ENTER07;	‘ Get the response
INPUT A$	‘ Screen shows 000 — Device Dependent Error no longer there
PRINT A$
PRINT#1,"SPOLL07	‘ Screen shows 4 — ESB bit no longer set (only Ready is set).

ChartScan User’s Manual C-17