CD1284 Datasheet, PDF (127/176 Pages) Intel Corporation – IEEE 1284-Compatible Parallel Interface Controller with Two High-Speed Asynchronous Serial Ports

IEEE 1284-Compatible Parallel Interface Controller — CD1284
Bit
Description
Carriage Return (CR) and New Line (NL) Processing: These three bits define the way that the CD1284
processes received CR and NL characters (x’0D and x’0A). The following table shows the actions performed:
IGNCR
ICRNL
INLCR
Action
0
0
0
No action.
0
0
1
Received NL changed to CR.
7:5
0
1
0
Received CR changed to NL.
0
1
1
Received CR changed to NL; NL changed to CR.
1
0
0
Received CR discarded.
1
0
1
Received CR discarded; NL changed to CR.
1
1
0
Received CR discarded.
1
1
1
Received CR discarded; NL changed to CR.
Break Processing: The CD1284 can handle received break characters in three ways:
IGNBRK
−BRKINT
Break Action
Received break generates an exception service request. End-
0
0
of-Break also generates an exception service request if EBD is
4:3
enabled in COR5.
0
1
Received break treated as a good NULL character.
1
0
Not used.
1
1
Received break discarded.
Parity (P), Framing (F), and Overrun (O) Error Special Processing: As with break characters, the CD1284
can treat error characters in several different ways, if enabled:
PEH[2]
PEH[1]
PEH[0]
Action
0
0
0
Received P/F/O error characters treated as exception data.
0
0
1
Received P/F/O error characters treated as good data.
0
1
0
Received P/F/O error characters discarded.
2:0
0
1
1
Received P/F/O error characters replaced with good NULL
characters.
Received P/F/O error characters are replaced with the two
1
0
0
character sequence x’FF-NULL-character. Good x’FF
characters are replaced with the two character sequence
x’FF-x’FF.
1
0
1
1
1
0
Not used.
1
1
1
Datasheet
127