mc68hc916y3 Freescale Semiconductor, Inc, mc68hc916y3 Datasheet - Page 427

• Manufacturer Part Number: mc68hc916y3
• Description: Mc68hc16y3 16 Bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

SCCR1 — SCI Control Register 1
D.7.5 SCI Control Register 1
Bit 15 — Not Implemented
MC68HC16Y3/916Y3
USER’S MANUAL
NOT USED
RESET:
15
where SCBR[12:0] is in the range of 1 to 8191.
Writing a value of zero to SCBR disables the baud rate generator. There are 8191
different bauds available. The baud value depends on the value for SCBR and the
system clock, as used in the equation above. Table D-35 shows possible baud rates
for a 16.78 MHz system clock. The maximum baud rate with this system clock speed
is 524 kbaud.
More accurate baud rates can be obtained by varying the system clock frequency with
the VCO synthesizer. Each VCO speed increment adjusts the baud rate up or down
by 1/64 or 1.56%.
SCCR1 contains SCI configuration parameters, including transmitter and receiver en-
able bits, interrupt enable bits, and operating mode enable bits. SCCR0 can be read
or written at any time. The SCI can modify the RWU bit under certain circumstances.
Changing the value of SCCR1 bits during a transfer operation disrupts operation.
LOOPS
14
0
WOMS
13
0
Baud Rate
500,00.00
38,400.00
32,768.00
19,200.00
Nominal
9,600.00
4,800.00
2,400.00
1,200.00
600.00
300.00
110.00
ILT
64.00
12
0
Table D-35 Examples of SCI Baud Rates
Freescale Semiconductor, Inc.
For More Information On This Product,
SCBR[12:0]
PT
11
0
PE
10
0
Go to: www.freescale.com
Baud Rate
524,288.00
37,449.14
32,768.00
19,418.07
9,532.51
4,809.98
2,404.99
1,199.74
Actual
599.87
299.94
110.01
64.00
M
9
0
=
-------------------------------------------------------------------------- -
32 SCI Baud Rate Desired
WAKE
8
0
Percent Error
TIE
–2.48
–0.70
–0.02
–0.02
–0.02
7
0
4.86
0.00
1.14
0.21
0.21
0.01
0.01
f
TCIE
sys
6
0
Value of SCBR
RIE
5
0
1,748
4,766
8,191
109
218
437
874
14
16
27
55
1
ILIE
4
0
TE
3
0
RE
2
0
$YFFC0A
MOTOROLA
RWU
1
0
D-49
SBK
0
0