參數(shù)資料
型號: PIC18F452-I/ML
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 44QFN
產(chǎn)品培訓(xùn)模塊: Asynchronous Stimulus
8-bit PIC® Microcontroller Portfolio
標(biāo)準(zhǔn)包裝: 45
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?。?/td> 256 x 8
RAM 容量: 1.5K x 8
電壓 - 電源 (Vcc/Vdd): 4.2 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-VQFN 裸露焊盤
包裝: 管件
配用: XLT44QFN2-ND - SOCKET TRAN ICE 44QFN/40DIP
444-1001-ND - DEMO BOARD FOR PICMICRO MCU
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.
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PIC18F452IPT 制造商:Microchip Technology Inc 功能描述:
PIC18F452T-E/ML 功能描述:8位微控制器 -MCU 40MHz 16KB Flash 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
PIC18F452T-I/L 功能描述:8位微控制器 -MCU 32KB 1536 RAM 34I/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
PIC18F452T-I/ML 功能描述:8位微控制器 -MCU 32KB 1536 RAM 34I/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
PIC18F452T-I/PT 功能描述:8位微控制器 -MCU 32KB 1536 RAM 34I/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