Quantum Data 801GC, 801GF, 801GX manual Queries, Output Queue

Command headers which require numeric data should be followed by at least one separator character (whitespace) then the data. Numeric data sent with a command is in decimal format. Numeric data can be represented in one of three methods; integer, float- ing point, and scaled floating point. The three meth- ods shown below would all represent the number 42.

Integer42

Floating Point 42.00

Scaled Floating Point 4.200E+01

Queries

Queries are comprised of a header followed imme- diately by a question mark (?). If there are any char- acters between the query header and the question mark character (including whitespace), a command error will result. Queries, upon completion of ex- ecution return a response message. A response message is comprised of the requested data termi- nated with an NL (ASCII 10) character. For example the following text would be returned in response to the HRAT? (horizontal rate query) message:

3.1500E+04<NL>

Note that the HRAT? query returns its parameter in exponential form. Possible returned parameter forms are integer, exponential, and string. The response form of each queryable message is shown at the end of this section.

Integer	form:	3965
Exponential form:		+3.965E+03
String	form:	"A string"

Output Queue

When a query is executed, the resulting response message is placed in an output queue where it can be read by the controller. The 801G* has an output queue that is 255 bytes long. When a message is present in the output buffer, the MAV (message

6-64 Chapter 6: Programming Model 801GC, 801GF & 801GX¥Rev. A