参数资料
型号: MC68HC05V7CB
厂商: FREESCALE SEMICONDUCTOR INC
元件分类: 微控制器/微处理器
英文描述: 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PDIP56
封装: SDIP-56
文件页数: 36/170页
文件大小: 980K
代理商: MC68HC05V7CB
MOTOROLA
SECTION 15: MESSAGE DATA LINK CONTROLLER
Page 116
MC68HC05V7 Specification Rev. 1.0
15.5.3
J1850 VPW SYMBOLS
Variable Pulse Width Modulation (VPW) is an encoding technique in which each bit is
defined by the time between successive transitions, and by the level of the bus between
transitions, active or passive. Active and passive bits are used alternately.
Each logic one or logic zero contains a single transition, and can be at either the active or
passive level and one of two lengths, either 64
s or 128 s (T
NOM at 10.4 kbps baud rate),
depending upon the encoding of the previous bit. The SOF, EOD, EOF and IFS symbols
will always be encoded at an assigned level and length. See Figure 15-11:
Each message will begin with an SOF symbol, an active symbol, and therefore each data
byte (including the CRC byte) will begin with a passive bit, regardless of whether it is a logic
one or a logic zero.
All VPW bit lengths stated in the following descriptions are typical values at a 10.4 kbps bit
rate.
128
s
Active
Passive
64
s
OR
Logic "0"
128
s
Active
Passive
64
s
OR
Logic "1"
200
s
Active
Passive
Start of Frame
200
s
End of Data
280
s
Active
Passive
End of Frame
280 s
Break
(a)
(b)
(c)
(d)
(e)
(f)
Figure 15-11 :
J1850 VPW Symbols
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
..
.
相关PDF资料
PDF描述
MC68HC711EA9VFS3 8-BIT, UVPROM, 3 MHz, MICROCONTROLLER, CQCC52
MPC7400RX350TX 32-BIT, 350 MHz, RISC PROCESSOR, CBGA360
MPC8250ACVRLHDX 32-BIT, 250 MHz, RISC PROCESSOR, PBGA516
MC68HC11L1VFU2 8-BIT, 2 MHz, MICROCONTROLLER, PQFP64
MC68HC08JL3CP 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PDIP28
相关代理商/技术参数
参数描述
MC68HC05X16 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:High-density complementary metal oxide semiconductor HCMOS) microcontroller unit
MC68HC05X32 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:High-density complementary metal oxide semiconductor HCMOS) microcontroller unit
MC68HC05X4 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit
MC68HC05X4CDW 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit
MC68HC05X4DW 制造商:FREESCALE 制造商全称:Freescale Semiconductor, Inc 功能描述:HCMOS Microcontroller Unit