
W83977F/ W83977AF
PRELIMINARY
Publication Release Date: March 1998
-11 -
Revision 0.58
1.5 Multi-Mode Parallel Port
The following pins have alternate functions, which are controlled by CR28 and L3-CRF0.
SYMBOL
PIN
I/O
FUNCTION
SLCT
18
IN
t
PRINTER MODE: SLCT
An active high input on this pin indicates that the printer is
selected. This pin is pulled high internally. Refer to description
of the parallel port for definition of this pin in ECP and EPP
mode.
OD
12
EXTENSION FDD MODE: WE2
This pin is for Extension FDD B; its function is the same as the
WE
pin of FDC.
OD
12
EXTENSION 2FDD MODE: WE2
This pin is for Extension FDD A and B; its function is the same
as the WE pin of FDC.
PRINTER MODE: PE
An active high input on this pin indicates that the printer has
detected the end of the paper. This pin is pulled high internally.
Refer to description of the parallel port for definition of this pin in
ECP and EPP mode.
PE
19
IN
t
OD
12
EXTENSION FDD MODE: WD2
This pin is for Extension FDD B; its function is the same as the
WD pin of FDC.
OD
12
EXTENSION 2FDD MODE: WD2
This pin is for Extension FDD A and B; its function is the same
as the WD pin of FDC.
PRINTER MODE: BUSY
An active high input indicates that the printer is not ready to
receive data. This pin is pulled high internally. Refer to
description of the parallel port for definition of this pin in ECP
and EPP mode.
BUSY
21
IN
t
OD
12
EXTENSION FDD MODE: MOB2
This pin is for Extension FDD B; the function of this pin is the
same as the MOB pin of FDC.
OD
12
EXTENSION 2FDD MODE: MOB2
This pin is for Extension FDD A and B; the function of this pin is
the same as the MOB pin of FDC.