FDC37B787QF SMSC [SMSC Corporation], FDC37B787QF Datasheet - Page 97

• Manufacturer Part Number: FDC37B787QF
• Description: Super I/O Controller with ACPI Support, Real Time Clock and Consumer IR
• Manufacturer: SMSC [SMSC Corporation]

The bit map of the Extended Parallel Port registers is:
Note 1: These registers are available in all modes.
Note 2: All FIFOs use one common 16 byte FIFO.
Note 3: The ECP Parallel Port Config Reg B reflects the IRQ and DRQ selected by the Configuration
ISA IMPLEMENTATION STANDARD
This specification describes the standard ISA
interface to the Extended Capabilities Port (ECP).
All ISA devices supporting ECP must meet the
requirements contained in this section or the port
will not be supported by Microsoft. For a
description of the ECP Protocol, please refer to the
IEEE 1284 Extended Capabilities Port Protocol
and ISA Interface Standard, Rev. 1.14, July 14,
1993. This document is available from Microsoft.
Description
The port is software and hardware compatible with
existing parallel ports so that it may be used as a
standard LPT port if ECP is not required. The port
is designed to be simple and requires a small
number of gates to implement. It does not do any
"protocol" negotiation, rather it provides an
automatic high burst-bandwidth channel that
data
ecpAFifo
dsr
dcr
cFifo
ecpDFifo
tFifo
cnfgA
cnfgB
ecr
Registers.
Addr/RLE
compress
nBusy
PD7
D7
0
0
intrValue
MODE
nAck
PD6
D6
0
0
Direction
PError
PD5
D5
0
Parallel Port IRQ
Parallel Port Data FIFO
nErrIntrEn
ackIntEn
ECP Data FIFO
Select
PD4
D4
Test FIFO
1
97
Address or RLE field
supports DMA for ECP in both the forward and
reverse directions.
Small FIFOs are employed in both forward and
reverse directions to smooth data flow and
improve the maximum bandwidth requirement.
The size of the FIFO is 16 bytes deep. The port
supports an automatic handshake for the standard
parallel port to improve compatibility mode transfer
speed.
The port also supports run length encoded (RLE)
decompression
Compression
identical bytes and transmitting an RLE byte that
indicates how many times the next byte is to be
repeated. Decompression simply intercepts the
RLE byte and repeats the following byte the
specified number of times. Hardware support for
compression is optional.
SelectIn
dmaEn
nFault
PD3
D3
0
serviceIntr
PD2
nInit
D2
is
0
0
Parallel Port DMA
(required)
accomplished
autofd
PD1
D1
full
0
0
in
strobe
empty
PD0
D0
0
0
by
hardware.
counting
Note
2
1
1
2
2
2