PARALLEL PORT
The FDC37C93xFR incorporates an IBM XT/AT
The parallel port also incorporates SMSC's
ChiProtect circuitry, which prevents possible
damage to the parallel port due to printer power-
up. The functionality of the Parallel Port is
achieved through the use of eight addressable
ports, with their associated registers and control
gating. The control and data port are read/write
by the CPU, the status port is read/write in the
EPP mode. The address map of the Parallel
Port is shown below:
compatible parallel port. This supports the
optional PS/2 type bi-directional parallel port
(SPP), the Enhanced Parallel Port (EPP) and
the Extended Capabilities Port (ECP) parallel
port modes.
Refer to the Configuration
Registers for information on disabling, power
down, changing the base address of the parallel
port, and selecting the mode of operation. The
FDC37C93xFR also provides
a mode for
support of the floppy disk controller on the
parallel port.
DATA PORT
BASE ADDRESS + 00H
BASE ADDRESS + 01H
BASE ADDRESS + 02H
BASE ADDRESS + 03H
EPP DATA PORT 0
EPP DATA PORT 1
EPP DATA PORT 2
EPP DATA PORT 3
BASE ADDRESS + 04H
BASE ADDRESS + 05H
BASE ADDRESS + 06H
BASE ADDRESS + 07H
STATUS PORT
CONTROL PORT
EPP ADDR PORT
The bit map of these registers is:
D0
PD0
D1
PD1
0
D2
PD2
0
D3
D4
D5
PD5
PE
D6
D7
Note
DATA PORT
PD3
PD4
SLCT
PD6
PD7
1
1
STATUS
PORT
TMOUT
nERR
nACK nBUSY
CONTROL
PORT
STROBE AUTOFD nINIT
SLC
PD3
PD3
PD3
PD3
PD3
IRQE
PD4
PD4
PD4
PD4
PD4
PCD
PD5
PD5
PD5
PD5
PD5
0
0
1
EPP ADDR
PORT
PD0
PD0
PD0
PD0
PD0
PD1
PD1
PD1
PD1
PD1
PD2
PD2
PD2
PD2
PD2
PD6
PD6
PD6
PD6
PD6
AD7
PD7
PD7
PD7
PD7
2,3
2,3
2,3
2,3
2,3
EPP DATA
PORT 0
EPP DATA
PORT 1
EPP DATA
PORT 2
EPP DATA
PORT 3
Note 1: These registers are available in all modes.
Note 2: These registers are only available in EPP mode.
Note 3: For EPP mode, IOCHRDY must be connected to the ISA bus.
87