Interrupt Type Codes
4-8
4.4.3
Statistics Overflow Interrupt. Int_type = 010b
This interrupt is given when one of the network statistics registers is halfway
filled. The driver:
-
Reads all the statistics registers, thereby clearing them
-
Acknowledges the interrupt, then exits
When reading the statistics registers, it is a good idea to use the Adr_Inc bit
in the DIO_ADR register. Using the Adr_Inc feature autoincrements the DIO
address by 4 on each DIO read. This feature saves on driver code and pro-
gramming time.
4.4.4
Rx EOF Interrupt. Int_type = 011b
An Rx EOF interrupt occurs when an Rx frame has been successfully re-
ceived. At this time there is no Rx interrupt threshold, so each frame immedi-
ately triggers an interrupt. On receiving an Rx EOF the driver:
-
Reads the Data_Address and Data_Count pointers
-
Determines how many bytes to copy to the Rx buffer, or whether there is
a buffer into which a frame can be copied
-
Copies data into the Rx buffer pointed to by the fragments (Data_Count,
Data_Address field pairs)
-
Passes control of the Rx buffer to the upper layer
-
Relinks the lists
-
Acknowledges the interrupts, then exits
4.4.5
Dummy Interrupt. Int_type = 100b
A dummy interrupt can be created by asserting the Req_Int bit in the
HOST_CMD register. This interrupt can be useful as a driver-definable inter-
rupt, as well as in hardware diagnostics. This interrupt ensures that the adapt-
er is open on the wire. The driver simply acknowledges this interrupt and exits.
Summary of Contents for ThunderLAN TNETE100A
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