參數(shù)資料
型號(hào): MC68HC05C8AVB
廠商: FREESCALE SEMICONDUCTOR INC
元件分類: 微控制器/微處理器
英文描述: 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PDIP42
封裝: PLASTIC, SDIP-42
文件頁(yè)數(shù): 60/116頁(yè)
文件大小: 781K
代理商: MC68HC05C8AVB
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)第14頁(yè)第15頁(yè)第16頁(yè)第17頁(yè)第18頁(yè)第19頁(yè)第20頁(yè)第21頁(yè)第22頁(yè)第23頁(yè)第24頁(yè)第25頁(yè)第26頁(yè)第27頁(yè)第28頁(yè)第29頁(yè)第30頁(yè)第31頁(yè)第32頁(yè)第33頁(yè)第34頁(yè)第35頁(yè)第36頁(yè)第37頁(yè)第38頁(yè)第39頁(yè)第40頁(yè)第41頁(yè)第42頁(yè)第43頁(yè)第44頁(yè)第45頁(yè)第46頁(yè)第47頁(yè)第48頁(yè)第49頁(yè)第50頁(yè)第51頁(yè)第52頁(yè)第53頁(yè)第54頁(yè)第55頁(yè)第56頁(yè)第57頁(yè)第58頁(yè)第59頁(yè)當(dāng)前第60頁(yè)第61頁(yè)第62頁(yè)第63頁(yè)第64頁(yè)第65頁(yè)第66頁(yè)第67頁(yè)第68頁(yè)第69頁(yè)第70頁(yè)第71頁(yè)第72頁(yè)第73頁(yè)第74頁(yè)第75頁(yè)第76頁(yè)第77頁(yè)第78頁(yè)第79頁(yè)第80頁(yè)第81頁(yè)第82頁(yè)第83頁(yè)第84頁(yè)第85頁(yè)第86頁(yè)第87頁(yè)第88頁(yè)第89頁(yè)第90頁(yè)第91頁(yè)第92頁(yè)第93頁(yè)第94頁(yè)第95頁(yè)第96頁(yè)第97頁(yè)第98頁(yè)第99頁(yè)第100頁(yè)第101頁(yè)第102頁(yè)第103頁(yè)第104頁(yè)第105頁(yè)第106頁(yè)第107頁(yè)第108頁(yè)第109頁(yè)第110頁(yè)第111頁(yè)第112頁(yè)第113頁(yè)第114頁(yè)第115頁(yè)第116頁(yè)
Serial Communications Interface (SCI)
MC68HC05C8A MC68HCL05C8A MC68HSC05C8A Data Sheet, Rev. 5.1
48
Freescale Semiconductor
9.4 SCI Operation
The SCI allows full-duplex, asynchronous, RS232 or RS422 serial communication between the MCU and
remote devices, including other MCUs. The SCI’s transmitter and receiver operate independently,
although they use the same baud-rate generator. This subsection describes the operation of the SCI
transmitter and receiver.
9.4.1 Transmitter
Figure 9-2 shows the structure of the SCI transmitter.
9.4.1.1 Character Length
The transmitter can accommodate either 8-bit or 9-bit data. The state of the M bit in SCI control register 1
(SCCR1) determines character length. When transmitting 9-bit data, bit T8 in SCCR1 is the ninth bit
(bit 8).
9.4.1.2 Character Transmission
During transmission, the transmit shift register shifts a character out to the PD1/TDO pin. The SCI data
register (SCDR) is the write-only buffer between the internal data bus and the transmit shift register.
Writing a logic 1 to the TE bit in SCI control register 2 (SCCR2) and then writing data to the SCDR begins
the transmission. At the start of a transmission, transmitter control logic automatically loads the transmit
shift register with a preamble of logic 1s. After the preamble shifts out, the control logic transfers the
SCDR data into the shift register. A logic 0 start bit automatically goes into the least significant bit position
of the shift register, and a logic 1 stop bit goes into the most significant bit position.
When the data in the SCDR transfers to the transmit shift register, the transmit data register empty
(TDRE) flag in the SCI status register (SCSR) becomes set. The TDRE flag indicates that the SCDR can
accept new data from the internal data bus.
When the shift register is not transmitting a character, the PD1/TDO pin goes to the idle condition, logic 1.
If software clears the TE bit during the idle condition, and while TDRE is set, the transmitter relinquishes
control of the PD1/TDO pin.
9.4.1.3 Break Characters
Writing a logic 1 to the SBK bit in SCCR2 loads the shift register with a break character. A break character
contains all logic 0s and has no start and stop bits. Break character length depends on the M bit in
SCCR1. As long as SBK is at logic 1, transmitter logic continuously loads break characters into the shift
register. After software clears the SBK bit, the shift register finishes transmitting the last break character
and then transmits at least one logic 1. The automatic logic 1 at the end of a break character is to
guarantee the recognition of the start bit of the next character.
9.4.1.4 Idle Characters
An idle character contains all logic 1s and has no start or stop bits. Idle character length depends on the
M bit in SCCR1. The preamble is a synchronizing idle character that begins every transmission.
相關(guān)PDF資料
PDF描述
MC68HCL05C8AB 8-BIT, MROM, MICROCONTROLLER, PDIP42
MC68HCL05C8AFB 8-BIT, MROM, MICROCONTROLLER, PQFP44
MC68HC05C8AVFB 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PQFP44
MC68HSC05C8CFN 8-BIT, MROM, 4.1 MHz, MICROCONTROLLER, PQCC44
MC68HSC05C8CFB 8-BIT, MROM, 4.1 MHz, MICROCONTROLLER, PQFP44
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MC68HC05C9 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:TECHNICAL DATA
MC68HC05C9A 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:Microcontrollers
MC68HC05C9AB 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:Microcontrollers
MC68HC05C9AFB 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:Microcontrollers
MC68HC05C9AFN 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:Microcontrollers