ICP DAS USA I-7521, User Manual

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I-7521/I-7522/I-7522A/I-7523/I-7524/I-7527 User’s Manual,Ver2.5 Aug.2015
105
5.3.27 ~AA3ETT

Description :
This function enables/disables the host watchdog timer and sets the value. The host
watchdog timer is designed for the software host watchdog. When the software host
watchdog is enabled, the host must send a
~** “HOST is OK” command (see Sec
5.3.23), to all modules before the timer expires. When the ~** command is received, the
host watchdog timer is reset and restarted. Using the ~AA2 command to read the host
watchdog status and value.

Syntax :
~AA3ETT[chk](CrLf)
~
Delimiter character
AA 2-character module address in HEX format. The valid range is from
00 to FF
E=0 Disables the host watchdog timer
E=1 Enables the host watchdog timer
TT
2-character timer value in HEX format. The valid range is from 00 to
FF. Units=0.1sec
[chk] 2-character checksum. If the checksum is disabled

no [chk]
(CrLf) End Character

Response : valid command

!AASTT[chk](CrLf)
invalid command

?AA[chk](CrLf)
no response

syntax error, communication error, or address error
! Delimiter character indicating a valid command
? Delimiter character indicating an invalid command
AA 2-character module address in HEX format
S=0 The host watchdog timer is disabled
S=1 The host watchdog timer is enabled
TT 2-character timer value in HEX format. The valid range is from 00 to
FF.Units=0.1 sec
[chk] 2-character checksum. If the checksum is disabled

no [chk]
(CrLf) End Character

Example :
command: ~013000(CrLf)
response : !01000(CrLf)
command: ~02310A(CrLf)
response : !0210A(CrLf)
Disables the host watchdog timer for
module 01
The host watchdog timer of module 02 is
enabled and is set to 0.1*10 =1 second.
For: I-7521/I-7522/I-7522A/I-7523/I-7524/I-7527