Siemens CP 243-2 - Manual (Page 71)

Command Interface
5-3
SIMATIC NET CP 243-2 AS-i Master
C79000-G8976-C142/02
Command Sequence
The diagram below shows the following:
S How to execute commands in the user program
S
How the CP 243-2 reacts to a command
Initial status
ASI_COM bit = 0
ASI_RESP bit = 0
Start command
Set ASI_COM bit = 1
Wait for response
ASI_RESP bit = ?
Response data valid
ASI_RESP bit = 1
detected
Evaluate response data
After evaluation, set
ASI_COM = 0
Ready to send command
detected
ASI_RESP bit = 0
detected
AS-i master
(user program) CP 243-2
(reaction to command)
Receives command
Detects that
response data
were evaluated
Signals command
executed
Sets ASI_RESP = 1
Ready for new command
Sets ASI_RESP = 0
Set command parameter
in the analog output area
Initial status
ASI_COM bit = 0
ASI_RESP bit = 0
Executes command
Figure 5-1