- Linux MultiMedia Studio Computer Accessories User Manual

Mint v4 PC Programming Guide
38
MN1278 05.2001
4.2 Events and Interrupt Control on NextMove PCI
The NextMove PCI controller requires a device driver to be installed on the host PC in order for communication
to be established between it and the controller. The use of device drivers makes it possible for interrupts from the
card to be trapped and handled. The Dual Port RAM interface allows the PC to interrupt the controller and the
controller to interrupts the host. Interrupt handling using the NextMove PCI controller is supported under both
Windows NT and Windows 95 and 98.
4.2.1 Writing and Installing an Interrupt Handler
When the controller interrupts the host PC the device driver will trap the interrupt and determine what ‘type’ of
event has occurred. Following this it will call the appropriate event handler.
NextMove can generate a number of events in response to certain situations:
•
Axis idle - an axis has become idle.
•
CAN 1 (CAN Open) – an event on CAN bus 1
• CAN 2 (Baldor CAN) – an event on CAN bus 2
• Comms – the comms location 1 to 5 has been written to
• DPR event – the user generated a DPR event ( see 4.2.3 Interrupting the Host from a Mint Program (
DPR Events ))
• Errors – an error occurred on the NextMove card
•
Fast position latch – an axis has latched position
•
Digital input active – a digital input has become active
•
Move buffer low - the numbers of moves in a move buffer drops below a specified threshold.
• Reset – the NextMove PCI card has reset
• Serial receive – the controller has put a character into its pseudo serial transmit buffer.
• Stop switch – a stop switch has become active
•
Timer – the timer event period has expired
The events are prioritised in the following order:
Priority Event
0: Highest Serial Receive
1 Error
2 CAN 1 (CANOpen)
3 CAN 2 (Baldor CAN)
4 Stop switch
5 Fast position latch