Server logs this error and continues with the next packet of data to the same device.

Acknowledge — The slave device has accepted the request and is processing it, but will require a long time to do so. This response is returned by some of the slave devices to prevent a time-out error at the Server. The Server notes the device as “sleeping” and waits for its response, rather than requerying the device. The length of time (in milliseconds) the Server waits for the response is referred to as the elapsed retry time. This parameter is set in the Server’s .ini file. When the elapsed retry time has passed, the Server will resume sending packets to the device.

Slave Device Busy — A slave device is busy processing internal computations. This message is similar to Acknowledge above. The Server marks the device as “sleeping” and will not transmit packets of data to the device until the elapsed retry time has passed.

Negative Acknowledge — A slave device cannot perform the program function in the query. An example might be a circuit breaker in local- control mode when the Server attempts to exercise an on/off command. The device will not permit remote control to override local control and will reply a Negative Acknowledge.

Memory Parity Error — The slave attempted to read extended memory but detected a parity error in the memory.

Unknown Error Code — The slave device has returned an unknown error code. Check the slave device manual for explanations of device- specific exception codes.

Failed to activate item(<logical device handle>, <Protocol Handle>)=>0

Server internal error. Please contact Customer Support.

Failed to create item (<logical device handle>) (<toolkit handle>) (<item name>) =>0

Possible causes are :

The item name is not spelled correctly on the client.

The item register(s) is (are) not configured in any of the register groups of the device type. Check the device type’s register-group configuration.

If the item name uses a mnemonic convention, then the mnemonic is not defined on the Server. Check the device type’s mnemonic configuration.

Failed to deactivate item(<logical device handle>, <Protocol Handle>)

Server internal error. Please contact Customer Support.

Failed to delete item(<logical device handle>, <Protocol Handle>)

Server internal error. Please contact Customer Support.

Initialization failed for <comm port>

The Server failed to open the communication port. Possible causes of this error are:

62 Chapter Five - Troubleshooting

DDE Server User’s Guide

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Black Box GEH-6510 manual Failed to delete itemlogical device handle, Protocol Handle