參數(shù)資料
型號: PIC18LF452T-I/L
廠商: Microchip Technology
文件頁數(shù): 37/134頁
文件大?。?/td> 0K
描述: IC MCU FLASH 16KX16 A/D 44PLCC
產(chǎn)品培訓(xùn)模塊: Asynchronous Stimulus
標(biāo)準(zhǔn)包裝: 500
系列: PIC® 18F
核心處理器: PIC
芯體尺寸: 8-位
速度: 40MHz
連通性: I²C,SPI,UART/USART
外圍設(shè)備: 欠壓檢測/復(fù)位,LVD,POR,PWM,WDT
輸入/輸出數(shù): 34
程序存儲器容量: 32KB(16K x 16)
程序存儲器類型: 閃存
EEPROM 大小: 256 x 8
RAM 容量: 1.5K x 8
電壓 - 電源 (Vcc/Vdd): 2 V ~ 5.5 V
數(shù)據(jù)轉(zhuǎn)換器: A/D 8x10b
振蕩器型: 外部
工作溫度: -40°C ~ 85°C
封裝/外殼: 44-LCC(J 形引線)
包裝: 帶卷 (TR)
2011 Microchip Technology Inc.
Preliminary
DS41609A-page 225
PIC16(L)F1508/9
21.6.13.1
Bus Collision During a Start
Condition
During a Start condition, a bus collision occurs if:
a)
SDA or SCL are sampled low at the beginning of
the Start condition (Figure 21-32).
b)
SCL is sampled low before SDAx is asserted
During a Start condition, both the SDAx and the SCL
pins are monitored.
If the SDA pin is already low, or the SCL pin is already
low, then all of the following occur:
the Start condition is aborted,
the BCL1IF flag is set and
the MSSP module is reset to its Idle state
The Start condition begins with the SDAx and SCLx
pins deasserted. When the SDAx pin is sampled high,
the Baud Rate Generator is loaded and counts down. If
the SCLx pin is sampled low while SDAx is high, a bus
collision occurs because it is assumed that another
master is attempting to drive a data ‘1’ during the Start
condition.
If the SDAx pin is sampled low during this count, the
BRG is reset and the SDAx line is asserted early
(Figure 21-34). If, however, a ‘1’ is sampled on the SDA
pin, the SDA pin is asserted low at the end of the BRG
count. The Baud Rate Generator is then reloaded and
counts down to zero; if the SCL pin is sampled as ‘0’
during this time, a bus collision does not occur. At the
end of the BRG count, the SCL pin is asserted low.
FIGURE 21-33:
BUS COLLISION DURING START CONDITION (SDAX ONLY)
Note:
The reason that bus collision is not a fac-
tor during a Start condition is that no two
bus masters can assert a Start condition
at the exact same time. Therefore, one
master will always assert SDAx before the
other. This condition does not cause a bus
collision because the two masters must be
allowed to arbitrate the first address fol-
lowing the Start condition. If the address is
the same, arbitration must be allowed to
continue into the data portion, Repeated
Start or Stop conditions.
SDAx
SCLx
SEN
SDAx sampled low before
SDAx goes low before the SEN bit is set.
S bit and SSPxIF set because
SSP module reset into Idle state.
SEN cleared automatically because of bus collision.
S bit and SSPxIF set because
Set SEN, enable Start
condition if SDAx = 1, SCLx = 1
SDAx = 0, SCLx = 1.
BCLxIF
S
SSPxIF
SDAx = 0, SCLx = 1.
SSPxIF and BCLxIF are
cleared by software
SSPxIF and BCLxIF are
cleared by software
Set BCLxIF,
Start condition. Set BCLxIF.
相關(guān)PDF資料
PDF描述
PIC18LF442T-I/L IC MCU FLASH 8KX16 A/D 44PLCC
PIC16HV540-04I/P IC MCU OTP 512X12 18DIP
PIC16LC781T-I/SO IC MCU OTP 1KX14 A/D D/A 20SOIC
PIC16LC782T-I/SS IC MCU OTP 2KX14 A/D D/A 20SSOP
PIC16C620A-04/SO IC MCU OTP 512X14 COMP 18SOIC
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
PIC18LF4539-I/ML 功能描述:8位微控制器 -MCU 24KB 1408 RAM 32I/O RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
PIC18LF4539-I/P 功能描述:8位微控制器 -MCU 24KB 1408 RAM 32I/O RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
PIC18LF4539-I/PT 功能描述:8位微控制器 -MCU 24KB 1408 RAM 32I/O RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
PIC18LF4539T-I/ML 功能描述:8位微控制器 -MCU 24KB 1408 RAM 32I/O RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
PIC18LF4539T-I/PT 功能描述:8位微控制器 -MCU 24KB 1408 RAM 32I/O RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT