参数资料
型号: P89C662HBBD
厂商: NXP SEMICONDUCTORS
元件分类: 微控制器/微处理器
英文描述: 80C51 8-bit Flash microcontroller family
中文描述: 8-BIT, FLASH, 33 MHz, MICROCONTROLLER, PQFP44
封装: 10 X 10 MM, 1.40 MM HEIGHT, PLASTIC, MS-026, SOT-389-1, LQFP-44
文件页数: 15/89页
文件大小: 491K
代理商: P89C662HBBD
Philips Semiconductors
Product data
P89C660/P89C662/P89C664/
P89C668
80C51 8-bit Flash microcontroller family
16KB/32KB/64KB ISP/IAP Flash with 512B/1KB/2KB/8KB RAM
2002 Oct 28
15
Arbitration and Synchronization Logic
In the Master Transmitter mode, the arbitration logic checks that
every transmitted logic 1 actually appears as a logic 1 on the I
2
C
bus. If another device on the bus overrules a logic 1 and pulls the
SDA line low, arbitration is lost, and SIO1 immediately changes from
master transmitter to slave receiver. SIO1 will continue to output
clock pulses (on SCL) until transmission of the current serial byte is
complete.
Arbitration may also be lost in the Master Receiver mode. Loss of
arbitration in this mode can only occur while SIO1 is returning a “not
acknowledge: (logic 1) to the bus. Arbitration is lost when another
device on the bus pulls this signal LOW. Since this can occur only at
the end of a serial byte, SIO1 generates no further clock pulses.
Figure 4 shows the arbitration procedure.
The synchronization logic will synchronize the serial clock generator
with the clock pulses on the SCL line from another device. If two or
more master devices generate clock pulses, the “mark” duration is
determined by the device that generates the shortest “marks,” and
the “space” duration is determined by the device that generates the
longest “spaces.” Figure 5 shows the synchronization procedure.
A slave may stretch the space duration to slow down the bus
master. The space duration may also be stretched for handshaking
purposes. This can be done after each bit or after a complete byte
transfer. SIO1 will stretch the SCL space duration after a byte has
been transmitted or received and the acknowledge bit has been
transferred. The serial interrupt flag (SI) is set, and the stretching
continues until the serial interrupt flag is cleared.
ACK
1. Another device transmits identical serial data.
SDA
1
2
3
4
8
9
SCL
(1)
(1)
(2)
(3)
2. Another device overrules a logic 1 (dotted line) transmitted by SIO1 (master) by pulling the SDA line low. Arbitration is
lost, and SIO1 enters the slave receiver mode.
3. SIO1 is in the slave receiver mode but still generates clock pulses until the current byte has been transmitted. SIO1 will
not generate clock pulses for the next byte. Data on SDA originates from the new master once it has won arbitration.
SU00967
Figure 4. Arbitration Procedure
(1)
SCL
(3)
(1)
SDA
MARK
DURATION
SPACE DURATION
(2)
1. Another service pulls the SCL line low before the SIO1 “mark” duration is complete. The serial clock generator is immediately
reset and commences with the “space” duration by pulling SCL low.
2. Another device still pulls the SCL line low after SIO1 releases SCL. The serial clock generator is forced into the wait state
until the SCL line is released.
3. The SCL line is released, and the serial clock generator commences with the mark duration.
SU00968
Figure 5. Serial Clock Synchronization
相关PDF资料
PDF描述
P89C664HBA 80C51 8-bit Flash microcontroller family
P89C664HBBD 80C51 8-bit Flash microcontroller family
P89C662 80C51 8-Bit Flash Microcontroller 32KB ISP/IAP FLASH with 1KB RAM(80C51 8位闪速微控制器,带16KB ISP/IAP闪速存储器和1KB RAM)
P89C668HBA 80C51 8-bit Flash microcontroller family 64KB ISP FLASH with 8KB RAM
P89C668HFA 80C51 8-bit Flash microcontroller family 64KB ISP FLASH with 8KB RAM
相关代理商/技术参数
参数描述
P89C662HBBD/00,557 制造商:NXP Semiconductors 功能描述:
P89C662HFA 制造商:PHILIPS 制造商全称:NXP Semiconductors 功能描述:80C51 8-bit Flash microcontroller family
P89C662HFA/00,512 功能描述:8位微控制器 -MCU 32K/1K FL 6 CLK ISP/IAP IND RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
P89C662HFBD 制造商:PHILIPS 制造商全称:NXP Semiconductors 功能描述:80C51 8-bit Flash microcontroller family
P89C662HFBD/00,557 功能描述:8位微控制器 -MCU 32K/1K FL 6CLK ISP/IAP QFP IND RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT