Advantech Adam - 4021, User Manual, Page: 182 / 286

ADAM-4000 Series User Manual 170
4080
7.2.2.8 $AA7N
Name Read/Clear Overflow Flag command
Description The command requests the module to return the status of
the overflow flag for either counter 0 or counter 1. Then
clear the flag afterwards.
Syntax $AA7N(cr)
$
is a delimiter character.
AA (range 00-FF) represents the 2-character hexadecimal
address that you will access to.
7 is the Read/Clear Overflow Flag command.
N determines the channel whose overflow flag status
should be read and cleared. When N = 0, it represents
counter 0. On the other hand, N = 1 represents counter 1
(cr) is the terminating character, carriage return (0Dh).
Response !AAV(cr) if the command is valid.
?AA(cr) if an invalid operation was entered.
There is no response if the module detects a syntax or
communication error, or even if the specified address does not exist.
!
is a delimiter character which indicates a valid command.
?
is a delimiter character which indicates an invalid command .
AA
(range 00-FF) represents the 2-character hexadecimal
address of the module.
V
represents the status of the Nth channel's overflow flag.
V = 1 means that the overflow flag has been set because the
counting has exceeded the maximum count.
V = 0 means that the overflow flag has not been set.
(cr)
is the terminating character, carriage return (0Dh).
Example
command: $1371(cr)
response: !131(cr)
The command requests the counter/frequency module at
address 13 to return the status of the overflow flag for
counter 1 and to reset it. The module replies with the
overflow flag for counter 1indicating overflow. Then it is being reset.