BCM Advanced Research
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I/O Subsystem
The I/O Subsystem consists of a single component from Winbond. The IN440EX uses
the Plug and Play Compatible Ultra I/O Controller “W83977TF”, this device provides
support for the ISA Plug-and-Play version 1.0a and includes the recommended
functionality to support Windows 95. Through internal configuration registers, each of
the W83977TF’s logical device’s I/O address, DMA channel and IRQ channel may be
programmed. There are 480 I/O address location options, 13 IRQ options and 3 DMA
channel options for each logical device.
The Ultra I/O device provides two (2) high speed UARTs compatible serial ports with
send/receive 16 Byte FIFOs or one IR port, one Multi-Mode Parallel Port with
ECP/EPP modes, and a Floppy/Tape Controller supporting up to 2.88MB transfer
rates.
Serial Ports
The IN440EX has two (2) UARTs compatible serial ports configured as Data Terminal
Equipment (DTE). The electrical characteristics are compliant with the
EIA-232-D
Serial Communications Specifications
. The serial ports may be remapped above other
installable serial ports or disabled through BIOS. As a minimum the first serial port
(COM1) must be capable of re-mapping to COM3. The second serial port (COM2)
must be able to be remapped to COM4. The serial ports I/O address can be relocated
within 480 different locations. The default address for COM1, COM2, COM3 and
COM4 are 3F8H, 338H, 2F8H and 238H respectively. 13 different IRQ options are
available to the serial ports.
One port (COM1) is available through a connector (J4) is located on the rear panel of
the system PWA. The second Serial Port (COM2) is available through a header on the
PWA.
Reference:
J4 (COM1)
Connector Type:
male, 9 pin metal shell D-SUB
Connector Part Number:
Amp 1-103322-5 or equivalent
Reference:
J13 (COM2)
Connector Type:
male, 2x5, 0.100” centerline, straight
Connector Part Number:
Amp 1-103322-5 or equivalent
