Symptoms

A Dealer has a problem with devices after booting the NetLinx system. He has approximately 100 devices (AXP-CPI16) connected on one system. After rebooting, the following debug messages were received:

"BAD CARD EDGE - Fast settle Bus - Clear Check Device "

Cause

After rebooting, there are some devices missing, and on some devices, the "input-channel-status" is also not correct. With approximately 20 devices, the system boots properly. Also, when the devices are added to the system slowly, there is no problem. It seems that the system is overloaded, and the master can't receive all the information from the devices.

Resolution

Try setting the DEVICE HOLDOFF in the NetLinx master to ON.

Device Holdoff on|off:

Sets the master to holdoff devices until all objects in the master are running. If set to ON, any messages sent to devices in DEFINE_START will be lost. When set to OFF, it prevents received messages from being lost in the master, upon startup.

This is a command sent from terminal or Telnet.

DEVICE HOLDOFF ON

This means the programmer cannot send commands to devices in startup code in the NetLinx program. In this case, online events would be used where needed, to configure devices. This should help prevent losing devices and device status on boot up.

Also, systems with this many devices potentially have a great amount of cable. Be sure that the total capacitance does not exceed the specifications of AxLink. 37,500μf is the maximum capacitance the system will tolerate and still run correctly. Adding a Slave Port Expander (AXB-SPE) would allow an increase of cable.​