NEC UPD98413 User Manual page 74

Receive FIFO overflow counter
If a receive FIFO overflow occurs, the µ PD98413 increments the reception FIFO overflow counter. If a reception
FIFO overflow occurs while a packet is being received, the µ PD98413 outputs it from the POS interface as an
error packet. At the end of the packet, the RERR pin is asserted for notification. The remaining data for the
packet that is entered after the reception FIFO overflow occurs is discarded internally.
After a reception FIFO overflow occurs, the µ PD98413 does not resume reception until a certain amount of free
area (settable in an appropriate register, programmable) is reserved in the reception FIFO. Any new packet that
otherwise would be received during the suspended reception is discarded internally (as in the case where a
reception FIFO overflow occurs at the beginning of a packet). In this case too, the reception FIFO overflow
counter is incremented.
Short size packet counter
The µ PD98413 allows you to set the minimum receive packet size (settable in an appropriate register,
programmable). If receiving a packet whose size is below the minimum, the µ PD98413 increments the short size
packet counter.
Long size packet counter
The µ PD98413 allows you to set the maximum receive packet size (settable in an appropriate register,
programmable). Upon receiving a packet whose size exceeds the maximum, the µ PD98413 increments the long
size packet counter.
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CHAPTER 3 FUNCTIONAL OUTLINE
PRELIMINARY
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