Intel 386 User Manual

Intel386™ EX EMBEDDED MICROPROCESSOR USER’S MANUAL
D-58
D.58 SSIOBAUD
SSIO Baud-rate Control
SSIOBAUD
(read/write)
Expanded Addr:
ISA Addr:
Reset State:
F484H
—
00H
7 0
BEN BV6 BV5 BV4 BV3 BV2 BV1 BV0
Bit
Number
Bit
Mnemonic
Function
7 BEN Baud-rate Generator Enable:
Setting this bit enables the baud-rate generator. Clearing this bit disables
the baud-rate generator, clears the baud-rate count value, and forces the
baud rate clock to zero.
6–0 BV6:0 Baud-rate Value:
The baud-rate value (BV) is the reload value for the baud-rate
generator’s seven-bit down counter. The baud-rate generator’s output is
a function of BV and the baud-rate generator’s input (BCLKIN), as
follows.
(Hz)
If you know the desired output baud-rate frequency, you can determine
BV as follows.
baud-rate output frequency (Hz)
BCLKIN
2BV 2+
----------------------=
BV
BCLKIN
2 baud-rate output frequency×
---------------------------------------------------------------------------------


1–=

Intel 386 Specifications

General

Architecture	x86
Clock Speed	12 MHz to 40 MHz
Transistor Count	275, 000
Data Bus Width	32-bit
Address Bus Width	32-bit
Instruction Set	x86
Introduced	1985
Maximum Memory	4 GB
Operating Modes	Real mode, Protected mode, Virtual 8086 mode
MMU	Yes
Voltage	5V
Model	Intel 386
Package	PGA
Process	1.5 μm to 1 μm