{"product_id":"rs485-pi","title":"RS485 Pi","description":"\u003cp\u003eThe RS485 Pi is a communication development board supporting the RS-485 serial protocol, designed to work with the Raspberry Pi and other compatible single-board computers.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eSoldering required! This product comes unassembled and unsoldered.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cdiv class=\"col span5\"\u003e\n\u003cul\u003e\n\u003cli\u003eRS-485 Half Duplex Port.\u003c\/li\u003e\n\u003cli\u003eUp to 250 kbps transfer rate.\u003c\/li\u003e\n\u003cli\u003eUse the Raspberry Pi to control external RS-485 devices.\u003c\/li\u003e\n\u003cli\u003eStackable with other Raspberry Pi accessory boards.\u003c\/li\u003e\n\u003cli\u003eMounting holes for use with the AB Electronics UK mounting kits (sold separately)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv\u003e\n\u003cp\u003eThe RS-485 port is connected to the UART port on the Raspberry Pi using a SN65HVD72 interface. The SN65HVD72 IC converts the 3.3V UART signals to RS-485 voltages allowing communication with RS-485 compatible devices over a DB9 serial cable or twisted pair cable. The RS-485 port can be accessed through the DB9 port or the solder points on the PCB.\u003c\/p\u003e\n\u003cp\u003eThe RS485 Pi contains protection against voltage spikes in the form of a TVS Diode and two 10-?, Pulse-Proof Thick-Film Resistors.\u003c\/p\u003e\n\u003cp\u003ePlease note that you can only use one RS485 Pi board on a Raspberry Pi. if stacking with other boards we recommend putting the RS485 Pi at the top of the stack due to the height of the DB9 connector.\u003c\/p\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable cellspacing=\"1\" cellpadding=\"1\" border=\"0\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eSupply Voltage\u003c\/td\u003e\n\u003ctd\u003e3.3V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLogic Voltage at GPIO Port\u003c\/td\u003e\n\u003ctd\u003e3.3V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDifferential Input Voltage at A \u0026amp; B\u003c\/td\u003e\n\u003ctd\u003e-12V to +12V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHigh-level input voltage\u003c\/td\u003e\n\u003ctd\u003e2V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLow-level input voltage\u003c\/td\u003e\n\u003ctd\u003e0.4V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSignalling Data Rate\u003c\/td\u003e\n\u003ctd\u003e250 kbps\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch2\u003eCompatibility Chart\u003c\/h2\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ctable class=\"compatibility\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eRaspberry Pi Model A \/ B (Rev 1 original)\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"compatibilityno\"\u003eNo\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRaspberry Pi 1 Model A+\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"compatibilityyes\"\u003eYes\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRaspberry Pi 1 Model B+\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"compatibilityyes\"\u003eYes\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRaspberry Pi 2 Model B\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"compatibilityyes\"\u003eYes\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRaspberry Pi 3 Model B *\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"compatibilityyes\"\u003eYes\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRaspberry Pi 4 Model B\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"compatibilityyes\"\u003eYes\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRaspberry Pi Zero \/ W \/ 2W\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"compatibilityyes\"\u003eYes\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e*You need to use the latest Raspbian Jessie release and disable the built in Bluetooth to use the RS485 Pi on the Raspberry Pi 3, see ourKB page for the config changes needed.\u003c\/p\u003e\n\u003ch2\u003eUsing RS-485\u003c\/h2\u003e\n\u003cp\u003eRS-485, also known as ANSI\/TIA\/EIA-485, TIA\/EIA-485 or EIA-485 is a standard used in serial communication systems. Equipment using the RS-485 standard can be used over long distances in noisy environments. Unlike RS232, the RS-485 standard allows for multiple devices to be connected on the same network. The recommended arrangement for connecting devices to an RS-485 network is to use a series on nodes connected along a line or bus with terminating resistors used at either end of the bus to reduce reflections.\u003c\/p\u003e\n\u003cp\u003eA 120-? resistor is included with the RS485 Pi which will need to be fitted if the board is connected to the end of the RS-485 bus. The diagram below shows a typical network of RS-485 devices.\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/www.abelectronics.co.uk\/docs\/stock\/raspberrypi\/rs485pi\/rs485network.svg?width=700\" alt=\"\"\u003e\u003c\/p\u003e\n\u003ch2\u003eConnecting to the RS-485 Port\u003c\/h2\u003e\n\u003cp\u003eThe RS-485 port on the RS485 Pi can be accessed through the male DB9 socket or the solder points on the PCB. The DB9 socket uses three wires as shown on the diagram below.\u003c\/p\u003e\n\u003ctable cellspacing=\"0\" cellpadding=\"0\" border=\"0\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003ctable cellspacing=\"0\" cellpadding=\"1\" border=\"0\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePin\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003eUsage\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003ctd\u003eN\/C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2\u003c\/td\u003e\n\u003ctd\u003eN\/C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e3\u003c\/td\u003e\n\u003ctd\u003eB\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e4\u003c\/td\u003e\n\u003ctd\u003eA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e5\u003c\/td\u003e\n\u003ctd\u003eGround\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e6\u003c\/td\u003e\n\u003ctd\u003eN\/C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e7\u003c\/td\u003e\n\u003ctd\u003eN\/C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e8\u003c\/td\u003e\n\u003ctd\u003eN\/C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e9\u003c\/td\u003e\n\u003ctd\u003eN\/C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/www.abelectronics.co.uk\/docs\/stock\/raspberrypi\/serialpiplus\/db9.svg?width=700\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003eDB9 connector as viewed from the front of the RS485 Pi\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"col span5\"\u003e\n\u003ch2\u003eSchematic\u003c\/h2\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/www.abelectronics.co.uk\/docs\/stock\/raspberrypi\/rs485pi\/rs485pi-schematic.png?width=700\" alt=\"Click to download\"\u003e\u003cbr\u003eClick to download schematic PDF.\u003c\/p\u003e\n\u003ch2\u003e\u003cbr\u003e\u003c\/h2\u003e\n\u003ch2\u003eMechanical Drawings\u003c\/h2\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/www.abelectronics.co.uk\/docs\/stock\/raspberrypi\/rs485pi\/rs485pi-mechanical.svg?width=700\" alt=\"Mechanical Drawing\"\u003e\u003c\/p\u003e\n\u003cp\u003eClick image to enlarge\u003c\/p\u003e\n\u003ch2\u003eAssembly Instructions\u003c\/h2\u003e\n\u003cp\u003eThe RS485 Pi is supplied with the 40 pin GPIO connector and the DB9 connector unsoldered.\u003c\/p\u003e\n\u003cp\u003eA 120R terminator resistor is included in the kit. This will be required if the RS485 Pi is used as an end node within an RS485 network.\u003c\/p\u003e\n\u003cp\u003eBefore using the RS485 Pi you will need to solder both connectors onto the PCB. We suggest soldering the 40 pin GPIO connector first and then the DB9 connector.\u003c\/p\u003e\n\u003cp\u003eTo make assembly easier we have designed a PCB header assembly jig which you can download and print.\u003c\/p\u003e\n\u003ch2\u003ePCB Header Assembly Jig\u003c\/h2\u003e\n\u003cp\u003eDownload and print our PCB Header Assembly Jig to hold your circuit board when soldering the header pins.\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/www.abelectronics.co.uk\/docs\/kb\/pcbassemblyjig\/icon-use.png?width=700\" alt=\"Use\"\u003e\u003c\/p\u003e\n\u003c\/div\u003e","brand":"ABelectronics","offers":[{"title":"Default Title","offer_id":44930705227865,"sku":"wpp1789671571436","price":15.33,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0736\/5289\/5833\/files\/rs485-pi_1.jpg?v=1789671601","url":"https:\/\/gymflexfit.shop\/products\/rs485-pi","provider":"My Store","version":"1.0","type":"link"}