1.上拉电阻(Pull-Up Resistor):上拉电阻将信号引脚连接到正电压源上,使引脚在空闲状态下保持高电平。上拉电阻的值通常为1kΩ到10kΩ。 2.下拉电阻(Pull-Down Resistor):下拉电阻将信号引脚连接到负电压源上,使引脚在空闲状态下保持低电平。下拉电阻的值通常也为1kΩ到10kΩ。 三、上下拉电阻的选择 在选择上...
请问ISO3088在应用的时候,总线A\B如果采用上下拉电阻,请问是A上拉、B下拉;还是B上拉、A下拉。其上下拉电阻取多大适合? Use 1-kΩ to 10-kΩ pullup and pulldown resistors for enable lines to limit noise currents in these lines during transient events. 这里的上下拉电阻是failsafe bias 电阻。一般是...
GPIO_Initure.Mode=GPIO_MODE_OUTPUT_PP; //推挽输出 GPIO_Initure.Pull=GPIO_PULLDOWN; //下拉 GPIO_Initure.Speed=GPIO_SPEED_HIGH; //高速 //GPIO_Initure.Alternate=GPIO_AF8_UART7; //复用为UART7 HAL_GPIO_Init(GPIOF,&GPIO_Initure); //初始化PF8 //USART 初始化设置 UART7_RS485Handler.In...
Standard interface RS485,pull-up and pull-down resistor,whose value is 4.7K,have been set to A/B line.Transmission Specifications Item Operating Conditions Value Data Rate 9600bps (max.)Transceiver Switching Delay The delay time from the receiving data switch to the send data :30μs(min.),...
(-50mV to -200mV) that complies fully with RS-485 specifications while guaranteeing that a 0V input produces a logic "High" at the receiver. The remaining termination resistor (approximately 200Ω) is connected between the differential lines. By eliminating the 330Ω pullup and pulldown ...
GPIO_InitStruct.Pull = GPIO_PULLDOWN; GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW; HAL_GPIO_Init(GPIOB, &GPIO_InitStruct); } /** * @brief RS485的DMA中断使能和优先级配置 */ static void RS485_DMA_Init(void) {/* DMA controller clock enable */ ...
RS-485 Pull-up andPull-down Resistor 2.2KΩ HardwareProtection ESD-IEC61000-4-2Level 4 Air±15KV, contact±8KV Surge-IEC61000-4-5level 3 ±2KV EFT-IEC61000-4-4Level 3 ±2KV Software Parameters Network Protocol IP/TCP/UDP/ARP/ICMP/IPV4/DHCP/DNS IP Mode Static IP, DHCP Modbus Gateway...
The RS485 communication circuit comprises a bus power supply, a MAX485 interface chip, an optical coupler U22, pull-up resistors R1 and R4, a pull-down resistor R2 and a resistor R3, wherein the first pin of the MAX485 interface chip is connected with the data receiving end of a CPU, ...
Single RS485isolated transceiver module RoHS FEATURES ●Small size,SMD package ●Integrated high efficiency isolated DC/DC converter ●Two-port isolation(2.5kVDC)●High baud rate up to19.2kbps ●Operating temperature range:-40℃to +85℃●The bus is able to support 64nodes at maximum ●Set ...
New generation RS-485 transceivers have an improved feature that includes true fail-safe receiver inputs. This eliminates the need for pull-up/pull-down resistors as shown in the previous example. If a transceiver is specified to have a true fail-safe feature this means that, the differential...