
The LINK™ Family Manual
Version 1.6 ©iButtonLink, LLC 2016
Page 44
Report Scan List
Command “ * ” (asterisk)
Command Compatible With:
LinkHub-E | LinkUSB
This command causes some LINK
TM
devices to report a scan list. If scanning is not active when
this command is entered, the response is a single-character carriage return.
A bus scanning function is included in many LINK
TM
products to scan and report the arrival or
departure of a new 1-Wire® device on a 1-Wire® bus. When turned ON using the “ $ ”
command, the scanning system continually performs “First” and “Next” device discovery
operations. It will build a table of device serial numbers, reporting up to eight (for LinkHub-S
and LinkHub-E) or 10 (for Link, LinkOEM, and LinkUSB) devices. The
arrival
will be reported
as a string with an exclamation point (!), a comma (,), and then the arriving device’s serial
number. The
departure
will be reported as a question mark (?), followed by a comma (,), and
then the serial number of the device departed from the bus. This will make sure that the device is
actually gone by doing multiple reads.
Scanning is terminated by “Reset,” “First,” “Next,” or a number of other operations.
The scanning system will not work properly if more than eight (for LinkHub-E) or 10 (for
LinkUSB) 1-Wire® or iButton® devices are present on the bus. Exceeding these numbers will
extend the Link’s memory capacity.
S
IMILAR
C
OMMANDS
:
•
“ $ “ – Arrival/Departure Scanning
!, 8000000202214928
!, 9A00000208AC5528
9A00000208AC5528
8000000202214928
Figure 18: The first two lines show the results of arrivals being scanned with
command " $ ". The next line is a line break, which was caused by command " * ".
Following the line break are the results of command “ * ”, which are the serial
numbers of the T-Probe