參數(shù)資料
型號: PIC18F85J50T-I/PT
廠商: Microchip Technology
文件頁數(shù): 36/61頁
文件大?。?/td> 0K
描述: IC PIC MCU FLASH 16KX16 80TQFP
產(chǎn)品培訓(xùn)模塊: Asynchronous Stimulus
PIC18 J Series MCU Overview
標(biāo)準(zhǔn)包裝: 1,200
系列: PIC® 18F
核心處理器: PIC
芯體尺寸: 8-位
速度: 48MHz
連通性: EBI/EMI,I²C,SPI,UART/USART,USB
外圍設(shè)備: 欠壓檢測/復(fù)位,LVD,POR,PWM,WDT
輸入/輸出數(shù): 65
程序存儲器容量: 32KB(16K x 16)
程序存儲器類型: 閃存
RAM 容量: 3.8K x 8
電壓 - 電源 (Vcc/Vdd): 2 V ~ 3.6 V
數(shù)據(jù)轉(zhuǎn)換器: A/D 12x10b
振蕩器型: 內(nèi)部
工作溫度: -40°C ~ 85°C
封裝/外殼: 80-TQFP
包裝: 帶卷 (TR)
配用: AC162087-ND - HEADER MPLAB ICD2 18F87J50 68/84
MA180021-ND - MODULE PLUG-IN 18F87J50 FS USB
AC164328-ND - MODULE SKT FOR 80TQFP
其它名稱: PIC18F85J50T-I/PTTR
Philips Semiconductors
Product data
P87LPC767
Low power, low price, low pin count (20 pin)
microcontroller with 4-kbyte OTP and 8-bit A/D converter
2002 Mar 25
38
More About UART Mode 0
Serial data enters and exits through RxD. TxD outputs the shift
clock. 8 bits are transmitted/received: 8 data bits (LSB first). The
baud rate is fixed at 1/6 the CPU clock frequency. Figure 31 shows
a simplified functional diagram of the serial port in Mode 0, and
associated timing.
Transmission is initiated by any instruction that uses SBUF as a
destination register. The “write to SBUF” signal at S6P2 also loads a
1 into the 9th position of the transmit shift register and tells the TX
Control block to commence a transmission. The internal timing is
such that one full machine cycle will elapse between “write to SBUF”
and activation of SEND.
SEND enables the output of the shift register to the alternate output
function line of P1.1 and also enable SHIFT CLOCK to the alternate
output function line of P1.0. SHIFT CLOCK is low during S3, S4, and
S5 of every machine cycle, and high during S6, S1, and S2. At
S6P2 of every machine cycle in which SEND is active, the contents
of the transmit shift are shifted to the right one position.
As data bits shift out to the right, zeros come in from the left. When
the MSB of the data byte is at the output position of the shift register,
then the 1 that was initially loaded into the 9th position, is just to the
left of the MSB, and all positions to the left of that contain zeros. This
condition flags the TX Control block to do one last shift and then
deactivate SEND and set T1. Both of these actions occur at S1P1 of
the 10th machine cycle after “write to SBUF.” Reception is initiated by
the condition REN = 1 and R1 = 0. At S6P2 of the next machine
cycle, the RX Control unit writes the bits 11111110 t o the receive shift
register, and in the next clock phase activates RECEIVE.
RECEIVE enable SHIFT CLOCK to the alternate output function line
of P1.0. SHIFT CLOCK makes transitions at S3P1 and S6P1 of every
machine cycle. At S6P2 of every machine cycle in which RECEIVE is
active, the contents of the receive shift register are shifted to the left
one position. The value that comes in from the right is the value that
was sampled at the P1.1 pin at S5P2 of the same machine cycle.
As data bits come in from the right, 1s shift out to the left. When the 0
that was initially loaded into the rightmost position arrives at the
leftmost position in the shift register, it flags the RX Control block to do
one last shift and load SBUF. At S1P1 of the 10th machine cycle after
the write to SCON that cleared RI, RECEIVE is cleared as RI is set.
More About UART Mode 1
Ten bits are transmitted (through TxD), or received (through RxD): a
start bit (0), 8 data bits (LSB first), and a stop bit (1). On receive, the
stop bit goes into RB8 in SCON. In the P87LPC767 the baud rate is
determined by the Timer 1 overflow rate. Figure 32 shows a
simplified functional diagram of the serial port in Mode 1, and
associated timings for transmit receive.
Transmission is initiated by any instruction that uses SBUF as a
destination register. The “write to SBUF” signal also loads a 1 into
the 9th bit position of the transmit shift register and flags the TX
Control unit that a transmission is requested. Transmission actually
commences at S1P1 of the machine cycle following the next rollover
in the divide-by-16 counter. (Thus, the bit times are synchronized to
the divide-by-16 counter, not to the “write to SBUF” signal.)
The transmission begins with activation of SEND which puts the
start bit at TxD. One bit time later, DATA is activated, which enables
the output bit of the transmit shift register to TxD. The first shift pulse
occurs one bit time after that.
As data bits shift out to the right, zeros are clocked in from the left.
When the MSB of the data byte is at the output position of the shift
register, then the 1 that was initially loaded into the 9th position is
just to the left of the MSB, and all positions to the left of that contain
zeros. This condition flags the TX Control unit to do one last shift
and then deactivate SEND and set TI. This occurs at the 10th
divide-by-16 rollover after “write to SBUF.”
Reception is initiated by a detected 1-to-0 transition at RxD. For this
purpose RxD is sampled at a rate of 16 times whatever baud rate
has been established. When a transition is detected, the
divide-by-16 counter is immediately reset, and 1FFH is written into
the input shift register. Resetting the divide-by-16 counter aligns its
rollovers with the boundaries of the incoming bit times.
The 16 states of the counter divide each bit time into 16ths. At the
7th, 8th, and 9th counter states of each bit time, the bit detector
samples the value of RxD. The value accepted is the value that was
seen in at least 2 of the 3 samples. This is done for noise rejection.
If the value accepted during the first bit time is not 0, the receive
circuits are reset and the unit goes back to looking for another 1-to-0
transition. This is to provide rejection of false start bits. If the start bit
proves valid, it is shifted into the input shift register, and reception of
the rest of the frame will proceed.
As data bits come in from the right, 1s shift out to the left. When the
start bit arrives at the leftmost position in the shift register (which in
mode 1 is a 9-bit register), it flags the RX Control block to do one
last shift, load SBUF and RB8, and set RI. The signal to load SBUF
and RB8, and to set RI, will be generated if, and only if, the following
conditions are met at the time the final shift pulse is generated.: 1.
R1 = 0, and 2. Either SM2 = 0, or the received stop bit = 1.
If either of these two conditions is not met, the received frame is
irretrievably lost. If both conditions are met, the stop bit goes into
RB8, the 8 data bits go into SBUF, and RI is activated. At this time,
whether the above conditions are met or not, the unit goes back to
looking for a 1-to-0 transition in RxD.
相關(guān)PDF資料
PDF描述
PIC18F45J10-I/P IC PIC MCU FLASH 16KX16 40DIP
PIC24FJ16GA002-I/SO IC PIC MCU FLASH 16K 28-SOIC
PIC18F25K22-I/SO MCU 8BIT 32KB FLASH 5.5V 28SOIC
PIC18F26K20-I/SS IC PIC MCU FLASH 32KX16 28-SSOP
PIC24F08KA102-I/ML IC PIC MCU FLASH 8K 28-QFN
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
PIC18F85J90-I/PT 功能描述:8位微控制器 -MCU 32KB Flash 2048BRAM 67I/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(shí)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
PIC18F85J90T-I/PT 功能描述:8位微控制器 -MCU 32KB Flash 2048bytes-RAM 67I/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(shí)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
PIC18F85J94-I/PT 制造商:Microchip Technology Inc 功能描述:80 PINS, 32KB FLASH, 4KB RAM, 16MIPS, NANOWATT XLP, LCD, USB - Trays
PIC18F85J94T-I/PT 制造商:Microchip Technology Inc 功能描述:80 PINS, 32KB FLASH, 4KB RAM, 16MIPS, NANOWATT XLP, LCD, USB - Tape and Reel 制造商:Microchip Technology Inc 功能描述:IC MCU 8BIT 32KB FLASH 80TQFP 制造商:Microchip Technology Inc 功能描述:8-bit Microcontrollers - MCU 80 pins, 32KB Flash, 4KB RAM, 16MIPS 制造商:Microchip Technology Inc 功能描述:80 pins, 32KB Flash, 4KB RAM, 16MIPS, nanoWatt XLP, LCD, USB, 80 TQFP 12x12x1mm
PIC18F85K22-E/PT 功能描述:8位微控制器 -MCU 32KB Flash 2KB RAM 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(shí)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