CD1284 Datasheet, PDF (53/176 Pages) Intel Corporation – IEEE 1284-Compatible Parallel Interface Controller with Two High-Speed Asynchronous Serial Ports

IEEE 1284-Compatible Parallel Interface Controller — CD1284
Figure 8. FIFO Timer Processing
BACKGROUND SCANNING
DETECTS NEW CHARACTER
ARRIVED
PUT CHARACTER IN FIFO
RELOAD TIMER
RESUME BACKGROUND
SCANNING LOOP
FROM OTHER
BACKGROUND PROCESSING
N
TIMER = 0
?
Y
FIFO EMPTY
?
Y
NO NEW DATA
TIMEOUT
ENABLED
?
Y
N
POST RECEIVE ‘GOOD DATA’
SERVICE REQUEST
N
NO NEW DATA
N
INTERNAL FLAG
ARMED
?
Y
CLEAR NONEWDATA
INTERNAL FLAG
POST RECEIVE EXCEPTION
SERVICE REQUEST
RESUME BACKGROUND
SCANNING LOOP
Datasheet
53