4 ssio baud-rate control register (ssiobaud), Figure 1318. ssio baud-rate control register (ssi – Intel 386 User Manual
Page 419

Intel386™ EX EMBEDDED MICROPROCESSOR USER’S MANUAL
13-20
13.3.4 SSIO Baud-rate Control Register (SSIOBAUD)
Use SSIOBAUD to enable the baud-rate generator and determine the baud-rate generator’s sev-
en-bit down counter’s reload value (BV).
Figure 13-18. SSIO Baud-rate Control Register (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
Ч
---------------------------------------------------------------------------------
1
–
=