Answer ID 33977 Status Released Access Level TechConnect Language English (US) Assigned To Not specified Products Drives & Motors Drive Communications & Accessories Industrial Communications & Networks DeviceNet I/O Chassis-based I/O Flex (1794) Categories General Date Created 01/10/2006 12:00 AM Last Updated 02/01/2011 11:29 AM Prev. TN# G142733457 Auto Translate No Overwrite No How a 1794-ADN configures itself for a FlexI/O rack of IO modules using Fresh Out of Box mode Question How a 1794-ADN configures itself for a FlexI/O rack of IO modules using Fresh Out of Box mode. Answer A 1794-ADN module fresh out of the box is already configured to factory defaults and this gives it a very unique behavior. After each power cycle, the 1794-ADN goes out on the FlexI/O rack and will identify what I/O modules are there. It will then use the default sizes shown in the table below for each module contained in its rack to determine the total Rx and Tx size for the entire rack. If the rack contents change, the 1794-ADN will declare an error, until the rack is either put back to its previous state or power is cycled to the 1794-ADN. If power is cycled to the 1794-ADN, it will dynamically reconfigure itself to the current contents of the rack. Be aware that this true “Fresh Out of the Box” mode is disabled whenever a Clear/Reset Memory & Upload function or a configuration download is done via the RSNetWorx for DeviceNet software. The only way to get the mode operational again, is to go into the Class Instance Editor of the RSNetWorx software and do a Reset Service 05, to Class 0xF, Instance 0, with a 1 as data. This takes the ADN back to Factory Defaults, thus re-enabling the Fresh Out of the Box mode. The behavior of the 1794-ADN changes slightly after a Clear/Reset Memory & Upload function is done at least once to the 1794-ADN from the FlexI/O applet inside the RSNetWorx software. The 1794-ADN will retain its configuration of the current FlexI/O rack, until another Clear/Reset Memory & Upload Function is done, at which time the 1794-ADN will re-configure itself depending on the new rack contents. It still uses the default sizes to determine its Tx and Rx sizes, so this configuration will be identical to that determined by the true Fresh Out of the Box mode, described in the first paragraph. Cycling Power will no longer have any effect on the 1794- ADN configuration. If a custom configuration is needed, such as trimming the Tx or Rx sizes of individual modules in the FlexI/O rack, then this can be easily done using the RSNetWorx software. Once this custom configuration is downloaded to the 1794-ADN, it will lock in that configuration. This configuration is stored in the 1794-ADN and if the ADN needs to be replaced later there are two scenarios possible. The first is to use the ADR feature in the master scanner to reconfigure the ADN. The second scenario is that the configuration will have to be downloaded, via RSNetWorx software, to the replacement 1794-ADN before it will operate the same as the original ADN. Important Note: You must disconnect the master scanner from the network or disable the scanlist entry for the FlexI/O adapter, in the master scanner, before attempting a Clear/Reset Memory & Upload function or a configuration download to the 1794- ADN. Otherwise the 1794-ADN will ignore the request. Page 1 of 3 Answer - How a 1794-ADN configures itself for a FlexI/O rack of IO modules using Fres ... 6/27/2011 https://rockwellautomation.custhelp.com/cgi-bin/rockwellautomation.cfg/php/admin/displa ...