W83627EHG Nuvoton Technology Corporation of America, W83627EHG Datasheet - Page 175

• Manufacturer Part Number: W83627EHG
• Description: IC I/O CONTROLLER 128-QFP
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of W83627EHG

• Applications: PC's, PDA's
• Interface: LPC
• Voltage - Supply: 3.3V
• Package / Case: 128-XFQFN
• Mounting Type: Surface Mount
• Pin Count: 128
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

10.3 Extended Capabilities Parallel (ECP) Port
This
W83627EHF/EHG/EF/EG parallel port may be used in standard printer mode if ECP is not required. It
provides an automatic high burst-bandwidth channel that supports DMA for ECP in both the forward
(host-to-peripheral) and reverse (peripheral-to-host) directions.
Small FIFOs are used in both forward and reverse directions to improve the maximum bandwidth
requirement. The size of the FIFO is 16 bytes. The ECP port supports an automatic handshake for the
standard parallel port to improve compatibility mode transfer speed.
The ECP port hardware supports run-length-encoded (RLE) decompression. Compression is
accomplished by counting identical bytes and transmitting an RLE byte that indicates how many times
the next byte is to be repeated. RLE compression is required; the hardware support is optional.
For more information about the ECP Protocol, please refer to the Extended Capabilities Port Protocol
and ISA Interface Standard.
The W83627EHF/EHG/EF/EG ECP supports the following modes.
The mode selection bits are bits 7-5 of the Extended Control Register.
10.3.1 ECP Register and Bit Map
MODE
000
001
010
011
100
101
110
111
port
is
SPP mode
PS/2 Parallel Port mode
Parallel Port Data FIFO mode
ECP Parallel Port mode
EPP mode (If this option is enabled in the CRF0 to select ECP/EPP mode)
Reserved
Test mode
Configuration mode
software-
and
hardware-compatible
W83627EHF/EF, W83627EHG/EG
- 164 -
DESCRIPTION
with
existing
parallel
ports,
so
the