SPI Programming Manual (G06.24+, H06.03+, J06.03+)

SPI Concepts and Protocol
SPI Programming Manual—427506-006
2-28
Responses
Extended GETVERSION Commands
A subsystem can provide additional features in its implementation of the
GETVERSION command:
•
The subsystem can allow the requester to specify a particular object type other
than NULL in order to retrieve the version of some subsystem component.
•
The subsystem can allow additional tokens in the command which prompt the
subsystem for additional information describing specific features supported by the
subsystem.
Responses
Every command sent to an SPI server results in a response. These terms and
concepts are central to understanding SPI responses:
•
Response—the sum of all information that an SPI server returns to the requester
as a result of processing a command. This information can be returned in a single
response message, or might require several response messages.
•
Response message—a single SPI message sent from an SPI server to the
requester to describe the outcome of command processing. A response message
can contain a single response record, multiple response records, or, in the case of
a segmented response, only part of a response record.
•
Response record—all information describing the application of a command to a
single object, or, if an error in the command prevented it from being applied to any
object, the response record contains general error information.
Types of Responses
Several types of responses result from various combinations of response records and
response messages:
Response
Type Consists of... Page
Simple One response record returned in a single response message. 2-29
Multirecord Multiple response records returned in a single response message. 2-30
Continued One or more response records returned in multiple response
messages.
2-34
Segmented A single response record returned a piece at a time in multiple
response messages (special form of continued response).
2-38
Empty Only the return code token. Also sometimes returned as the last
message in a continued response. (Special form of simple
response.)
2-41