參數(shù)資料
型號: MC68CK338CPV14
廠商: FREESCALE SEMICONDUCTOR INC
元件分類: 微控制器/微處理器
英文描述: 32-BIT, 14.4 MHz, MICROCONTROLLER, PQFP144
封裝: PLASTIC, TQFP-144
文件頁數(shù): 105/133頁
文件大?。?/td> 944K
代理商: MC68CK338CPV14
MC68CK338
MOTOROLA
MC68CK338TS/D
73
SCCR0 contains a baud rate selection parameter. Baud rate must be set before the SCI is enabled. The
CPU can read and write this register at any time.
Bits [15:13] — Not Implemented
SCBR[12:0] — Baud Rate
SCI baud rate is programmed by writing a 13-bit value to BR. The baud rate is derived from the MCU
system clock by a modulus counter.
The SCI receiver operates asynchronously. An internal clock is necessary to synchronize with an in-
coming data stream. The SCI baud rate generator produces a receiver sampling clock with a frequency
16 times that of the expected baud rate of the incoming data. The SCI determines the position of bit
boundaries from transitions within the received waveform, and adjusts sampling points to the proper po-
sitions within the bit period. Receiver sampling rate is always 16 times the frequency of the SCI baud
rate, which is calculated as follows:
or
where SCBR[12:0] is in the range {1, 2, 3, …, 8191}
Writing a value of zero to SCBR[12:0] disables the baud rate generator.
Table 43 lists the SCBR[12:0] settings for standard and maximum baud rates using a 14.44 MHz sys-
tem clock.
SCCR0 — SCI Control Register 0
$YFFC08
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
SCBR[12:0]
RESET:
0
1
0
Table 43 SCI Baud Rates
Nominal Baud Rate
Actual Rate with
14.44 MHz Clock
SCBR[12:0] Value
64
64.0
$1B8B
110
110.0
$1006
300
300.0
$05E0
600
600.1
$02F0
1200
1200.1
$0178
2400
2400.3
$00BC
4800
4800.5
$005E
9600
9601.1
$002F
19200
18802.1
$0018
38400
37604.2
$000C
76800
75208.3
$0006
Maximum rate
451250.0
$0001
SCI Baud Rate
System Clock
32
() SCBR[12:0]
()
------------------------------------------------
=
SCBR[12:0]
System Clock
32
SCI Baud Rate Desired
×
---------------------------------------------------------------------------
=
F
re
e
sc
a
le
S
e
m
ic
o
n
d
u
c
to
r,
I
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
n
c
..
.
相關PDF資料
PDF描述
MC68EN360CRC25 32-BIT, 25 MHz, RISC MICROCONTROLLER, CPGA241
MC68F333FE 32-BIT, FLASH, 16.78 MHz, MICROCONTROLLER, CQFP160
MC68F333FC 32-BIT, FLASH, 16.78 MHz, MICROCONTROLLER, PQFP160
MC68HC000L12F 16-BIT, 16.67 MHz, MICROPROCESSOR, CDIP64
MC68HC000L16 16-BIT, 16.67 MHz, MICROPROCESSOR, CDIP64
相關代理商/技術參數(shù)
參數(shù)描述
MC68CK338CPV14B1 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:32-Bit Modular Microcontroller
MC68CM16Z1 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:M68HC16Z Series
MC68CM16Z1CFC16 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:M68HC16Z Series
MC68CM16Z1CPV16 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:M68HC16Z Series
MC68E360VR25VLR2 功能描述:微處理器 - MPU QUICC ETHRN RoHS:否 制造商:Atmel 處理器系列:SAMA5D31 核心:ARM Cortex A5 數(shù)據(jù)總線寬度:32 bit 最大時鐘頻率:536 MHz 程序存儲器大小:32 KB 數(shù)據(jù) RAM 大小:128 KB 接口類型:CAN, Ethernet, LIN, SPI,TWI, UART, USB 工作電源電壓:1.8 V to 3.3 V 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:FBGA-324