Z183 EMAC Board
User Manual
9
UM008301-0401
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uint *intrvec is a pointer to an interrupt vector table entry as determined by
the Z183 hardware interrupt line that is used to connect to the add-on board
interrupt output, the value programmed into the I and IL registers of the
Z183.
The driver places the address of its interrupt handler into the word that this
argument points to.
Once inside its interrupt service routine, the driver prevents its own Ethernet
add-on board peripheral from issuing further interrupts and re-enables the
general interrupts using an EI instruction. This allows minimum latency on
other real-time interrupts in the Z183 microprocessor programming.
Approximately 15 instructions on entry and a similar amount of instructions
on exit are executed with a DI (general master interrupt disable) instruction.
The transmit and receive function callbacks are issued with all other general
interrupts enabled.
extern void Reset8900(void);
This function resets the Ethernet MAC driver and hardware. Use Init8900( ) to
reactivate the Ethernet MAC hardware and driver. However, this is not a
hardware reset. Issuing this reset has no effect on the RESET button on the
Z183 board. The EMAC board remains addressable and accessible from
software.
Note:
The driver is unaware of the exact mechanism that causes its interrupt to be vectored to the
location specified by this pointer. You should check all the associated Z183 register programming,
as is necessary in an application scenario. Refer to the add-on board hardware manual for details
on wiring the interrupt signal between the add-on board and the Z183 board.