PARALLEL PORT
The LPC47B27x incorporates an IBM XT/AT 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 LPC47B27x also provides a mode for support of the floppy disk controller on the parallel port.
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:
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
D1
D2
PD2
0
D3
PD3
nERR
SLC
D4
D5
PD5
PE
D6
PD6
nACK
0
D7
PD7
nBUSY
0
Note
DATA PORT
PD0
PD1
0
PD4
1
1
1
STATUS PORT TMOUT
SLCT
IRQE
CONTROL
PORT
STROBE AUTOFD
nINIT
PCD
EPP ADDR
PORT
PD0
PD0
PD0
PD0
PD0
PD1
PD1
PD1
PD1
PD1
PD2
PD2
PD2
PD2
PD2
PD3
PD3
PD3
PD3
PD3
PD4
PD4
PD4
PD4
PD4
PD5
PD5
PD5
PD5
PD5
PD6
PD6
PD6
PD6
PD6
PD7
PD7
PD7
PD7
PD7
2
2
2
2
2
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.
Table 39 - Parallel Port Connector
HOST
CONNECTOR
PIN NUMBER
STANDARD
nStrobe
PD<0:7>
nAck
Busy
PE
EPP
ECP
1
83
68-75
80
nWrite
nStrobe
2-9
10
11
12
PData<0:7>
Intr
PData<0:7>
nAck
79
nWait
Busy, PeriphAck(3)
PError,
78
(User Defined)
nAckReverse(3)
Select
13
14
77
82
SLCT
nALF
(User Defined)
nDatastb
nAutoFd,
HostAck(3)
15
16
17
81
66
67
nError
nInit
(User Defined)
nRESET
nFault(1)
nPeriphRequest(3)
nInit(1)
nReverseRqst(3)
nSelectIn(1,3)
nSLCTIN
nAddrstrb
(1) = Compatible Mode
SMSC LPC47B27x
- 75 -
Rev. 08-10-04
DATASHEET
SMSC [ SMSC CORPORATION ]
