Sys Tec Electronic USB-CANmodul, System Manual

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USB-CANmodul
30
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SYS TEC electronic GmbH 2001 L-487e_6
After starting the application program and loading the DLL, the
software is now in the DLL_INIT state. Concurrently,
all required
resources for the DLL have been created.
Calling the library function UcanInitHardware () causes the software
to change into the HW_INIT state. This state contains all resources
required for communication with the USB-CANmodul. It is not
possible to transmit or to receive CAN messages in this state.
If the application software calls the library function UcanInitCan ()
the state changes into CAN_INIT. In this state it is possible to
transmit or to receive CAN messages.
Return with the library function UcanDeinitCan () into the state
HW_INIT and with the library function UcanDeinitHardware () into
the state DLL_INIT. It is possible to close the application program
only after this sequence is completed.
Note: Make sure to return to the state DLL_INIT before closing
the application program.
DLL loaded
DLL unloaded
DLL_INIT HW_INIT CAN_INIT
UcanInitHardware() UcanInitCan()
UcanDeinitHardware() UcanDeinitCan()
Figure 12: Software State Diagram