{"product_id":"ms2548-ttl-rs485-module-5v","title":"MS2548 TTL to RS485 Auto Direction Module - 5V","description":"\u003cdiv class=\"nznpd\"\u003e\n\u003cdiv class=\"nznpd__lead\"\u003e\n\u003cp class=\"nznpd__intro\"\u003eConnect a microcontroller UART to a two-wire RS485 bus with this MS2548 module. It runs from 5V, and the MS2548 transceiver switches between transmit and receive by itself, so no direction-control pin is needed. Its TXD and RXD pins use 5V logic, so it wires straight to an Arduino Uno or other 5V board. With a 3.3V board such as an ESP32, add a level shifter on both lines.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003csection class=\"nznpd__block\"\u003e\n\u003ch3 class=\"nznpd__h\"\u003eSpecifications\u003c\/h3\u003e\n\u003cdiv class=\"nznpd__specs\"\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eBoard marking\u003c\/span\u003e\u003cstrong\u003eHW-144\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eTransceiver\u003c\/span\u003e\u003cstrong\u003eMS2548\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eModule supply\u003c\/span\u003e\u003cstrong\u003e5V DC (4.5 to 5.5V)\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eLogic level\u003c\/span\u003e\u003cstrong\u003e5V UART\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eTTL interface\u003c\/span\u003e\u003cstrong\u003eVCC, TXD, RXD, GND\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eRS485 interface\u003c\/span\u003e\u003cstrong\u003eD+\/A, D-\/B, GND\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eBus mode\u003c\/span\u003e\u003cstrong\u003eTwo-wire half duplex\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eDirection control\u003c\/span\u003e\u003cstrong\u003eAutomatic, in the transceiver\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eBus loading\u003c\/span\u003e\u003cstrong\u003e1\/4 unit load, up to 128 nodes\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eStatus LEDs\u003c\/span\u003e\u003cstrong\u003ePower, TXD and RXD\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eTermination\u003c\/span\u003e\u003cstrong\u003e120 ohm via 120_S bridge\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eBoard size\u003c\/span\u003e\u003cstrong\u003eAbout 54 x 22 mm\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\n\u003csection class=\"nznpd__block\"\u003e\n\u003ch3 class=\"nznpd__h\"\u003eDatasheets\u003c\/h3\u003e\n\u003cdiv class=\"nznpd__ds\"\u003e\n\u003ca class=\"nznpd__dsbar\" href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0664\/6127\/0112\/files\/MS2548-TTL-RS485-Module-5V-Datasheet-v1.pdf\" target=\"_blank\" rel=\"noopener\" aria-label=\"Download the MS2548 TTL to RS485 5V module datasheet (PDF)\"\u003e\n\u003csvg width=\"20\" height=\"20\" viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"\u003e\u003cpath d=\"M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z\"\u003e\u003c\/path\u003e\u003cpolyline points=\"14 2 14 8 20 8\"\u003e\u003c\/polyline\u003e\u003c\/svg\u003e\n\u003cspan\u003eFull technical datasheet\u003c\/span\u003e\n\u003cspan class=\"nznpd__dsmeta\"\u003ePDF\u003csvg width=\"17\" height=\"17\" viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"\u003e\u003cpath d=\"M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4\"\u003e\u003c\/path\u003e\u003cpolyline points=\"7 10 12 15 17 10\"\u003e\u003c\/polyline\u003e\u003cline x1=\"12\" y1=\"15\" x2=\"12\" y2=\"3\"\u003e\u003c\/line\u003e\u003c\/svg\u003e\u003c\/span\u003e\n\u003c\/a\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\n\u003csection class=\"nznpd__block\"\u003e\n\u003ch3 class=\"nznpd__h\"\u003eWhat's in the box\u003c\/h3\u003e\n\u003cdiv class=\"nznpd__included\"\u003e\n\u003cdiv class=\"nznpd__qty\"\u003e1×\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cstrong\u003eMS2548 TTL to RS485 module\u003c\/strong\u003e\u003cp\u003eRed HW-144 board with a fitted right-angle 4-pin header and a green 3-way screw terminal.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\n\u003csection class=\"nznpd__block\"\u003e\n\u003ch3 class=\"nznpd__h\"\u003eGreat for\u003c\/h3\u003e\n\u003cdiv class=\"nznpd__uses\"\u003e\n\u003cdiv class=\"nznpd__use\"\u003eReading a Modbus RTU energy meter from an Arduino\u003c\/div\u003e\n\u003cdiv class=\"nznpd__use\"\u003eTalking to a VFD or PLC serial port\u003c\/div\u003e\n\u003cdiv class=\"nznpd__use\"\u003ePolling RS485 sensors over a long cable\u003c\/div\u003e\n\u003cdiv class=\"nznpd__use\"\u003eLinking two microcontrollers across a workshop\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\n\u003csection class=\"nznpd__block\"\u003e\n\u003cdiv class=\"nznpd__qs\"\u003e\n\u003ch3\u003eWiring \u0026amp; getting started\u003c\/h3\u003e\n\u003col class=\"nznpd__steps\"\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eConnect power with the circuit off\u003c\/strong\u003e\u003cp\u003eConnect a regulated 5V supply to VCC and join the controller and module grounds. Do not run it from 3.3V.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eConnect the UART\u003c\/strong\u003e\u003cp\u003eConnect controller TX to TXD and controller RX to RXD. On a 3.3V board such as an ESP32 or Pico, run both lines through a bidirectional level shifter.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eConnect the RS485 bus\u003c\/strong\u003e\u003cp\u003eConnect D+\/A to the remote A or + terminal and D-\/B to the remote B or - terminal. Keep the polarity the same along the whole bus.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eSet termination and start slow\u003c\/strong\u003e\u003cp\u003eBridge 120_S only when this module is at a physical end of the cable. Start at 9600 baud and raise the speed once replies are reliable.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\u003c\/div\u003e","brand":"NZN Electronics","offers":[{"title":"Default Title","offer_id":67593363095648,"sku":"MOD-MS2548-RS485","price":4.49,"currency_code":"NZD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0664\/6127\/0112\/files\/ms2548-ttl-rs485-module-5v-hero.png?v=1790930951","url":"https:\/\/www.nznelectronics.co.nz\/products\/ms2548-ttl-rs485-module-5v","provider":"NZN Electronics","version":"1.0","type":"link"}