RTEMS Network Supplement
This thread is event driven. Each time a DEC PCI board interrupt occurs, the handler checks if this is a receive interrupt and send an event ``reception'' to the receiver thread which looks into the entire buffer descriptors ring the ones that contain a valid incoming frame (bit OWN=0 means descriptor belongs to host processor). Each valid incoming ethernet frame is sent to the protocol stack and the buffer descriptor is given back to the DEC board (the host processor reset bit OWN, which means descriptor belongs to 21140).
RTEMS Network Supplement
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