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Basic Device Manual AS-i ControllerE M4 Target V15
2015-10-30
Function
Introduction AS-i data
29
Command channel: description
General structure:
Channel CmdOut (requests from the user program to the operating system)
Word no.
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
echo byte request *)
request output *)
/ status input *)
1
command code
2…16
data
17
reserved
18
reserved
Channel CmdResp (responses of the operating system for the user program)
Word no.
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
echo byte response *)
status input *)
1
command code
2…16
data / error code
17
reserved
18
reserved
The field "request output / status input" in the channel "CmdOut" synchronises the process.
*) After the user program has entered a request in the command channel the operating system
responds with "_PC_CMD_ACKN" in the output and input buffer. The command is now processed. As
soon as the response is available the operating system enters a value greater than
"_PC_CMD_ACKN" (= signal "command processing finished"). In this case the "echo byte request" is
also copied to the "echo byte response". So the user program can detect a response even if the
command code has not changed since the last command.
Valid values of "request output / status input"
Value
Symbolic name
Description
65
h
_PC_CMD_REQ
Command request by the user program
66
h
_PC_CMD_DETECT
Command request detected by the operating system
6A
h
_PC_CMD_ACKN
Command read and started by the operating system
6B
h
_
PC_CMD_ERROR
Result of the command incorrect, error code command-specific
6C
h
_PC_CMD_TIMEOUT
timeout during the command processing
6D
h
_
PC_CMD_IDLE
Reserved for test purposes
6E
h
_PC_CMD_INVALID
Unknown command, execution stopped
6F
h
_PC_CMD_READY
Command executed, data in the response buffer valid
