AC4790-200A-485 Laird Technologies, AC4790-200A-485 Datasheet
AC4790-200A-485
Specifications of AC4790-200A-485
Related parts for AC4790-200A-485
AC4790-200A-485 Summary of contents
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... Contents AC4790 TRANSCEIVER MODULE 1 AC4790 features 1 Overview 1 SPECIFICATIONS 3 Pin Definitions 5 Electrical Specifications 7 THEORY OF OPERATION 8 Masterless Architecture 8 Modes of Operation 8 Transmit Mode 8 Receive Mode 9 Command Mode 10 API CONTROL 11 API Transmit Packet 12 API Send Data Complete 12 API Receive Packet 12 SERIAL INTERFACE 14 Serial Communications 14 Asynchronous Operation 14 ...
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Copyright © 2007 Laird Technology, Inc. All rights reserved. The information contained in this manual and the accompanying software programs are copyrighted and all rights are reserved by Laird Technology, Inc. Laird Technology, Inc. reserves the right to make periodic ...
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Revision Description Version 1.0 2/21/05 - Initial Release Version Version 1.1 3/4/05 - Updated Session Count Truth Table Version 1.2 4/26/05 - Updated Transmit Mode Section Version 1.3 3/17/06 - Corrected API Send Data Complete. Added Australian Channels. Added 1x1 ...
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... Advanced configuration available using AT commands The AC4790 is a member of Laird Technology’s ConnexRF OEM transceiver family. The AC4790 is a cost effective, high performance, frequency hopping spread spectrum transceiver; designed for integration into OEM systems operating under FCC part 15.247 regulations for the 900 MHz ISM band. ...
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... The OEM is responsible for ensuring the final product meets all appropriate regulatory agency requirements listed herein before selling any product. Note: Unless mentioned specifically by name, the AC4790 modules will be referred to as the “radio” or “transceiver”. Individual naming is used to differentiate product specific features. The host (PC/Microcontroller/Any device to which ...
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... AC4790-1000: 743mW typical Supply Voltage AC4790-1x1: 3.3V, ±50mV ripple AC4790-200: 3.3 – 5.5V, ±50mV ripple AC4790-1000*: Pin 10: 3.3 – 5.5V ±50mV ripple * Pins 10 and 11 may be tied together, provided the supply voltage never falls below 3.3 V and is capable of supplying 1 current. Sensitivity -100dBm typical @ 76.8kbps RF Data Rate -110dBm typical @ 76 ...
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... Physical Transceiver with MMCX Connector: 1.65” x 1.9” x 0.20” Transceiver with Integral Antenna: 1.65” x 2.65” x 0.20” AC4790-1x1: 1.00” x 1.00” x 0.162” Certifications AC4790-200A AC4490-200/AC4490LR-200 KQLAC4490-100 KQL4x90-200 ...
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... The AC4790 has a simple interface that allows OEM Host communications with the transceiver. The table below shows the connector pin numbers and associated functions. The I/O direction is with respect to the transceiver. All outputs are 3.3VDC levels and inputs are 5VDC TTL (with the exception of AC4790-1x1 and AC4790-1000 transceivers which have 3 ...
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... N When ordered with a RS-485 interface (not available on the AC4790-1x1). 2. Must be tied to VCC or GND if not used. Should never be permitted to float used, requires a shunt 0.1μF capacitor at pin 15 followed by a series 1k resistor Signal Type Name O RSSI Received Signal Strength - An analog output giving an instantaneous indication of received signal strength ...
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... AC47901x1 / AC4790-1000M High Signal Name Min. RS485A/B N/A RXD 2.31 GI0 2.31 RTS 2.31 Test 2.31 GI1 2.31 UP_RESET 0.8 Command/Data 2. N Module Signal Name Pin GO0 1 TXD 2 RS485A/B 2,3 CTS 7 GO1 9 RSSI 13 Session Status 20 GO0 1 High Low Low High High Max ...
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... The AC4790 has three different operating modes; Receive, Transmit, & Command Mode. If the transceiver is not communicating with another radio, it will be in Receive Mode actively listening for a sync pulse from another transceiver. If the radio determines that broadcast or addressed sync pulse, it will respond by going into session with the radio ...
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Session Count is equal to Session Count Refresh (EEPROM address 0xC4) + number of broadcast attempts (EEPROM address 0x4D). Once the radio exits the Session it returns to the default Receive Mode ...
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Note: This is the default case with which the radio ships and works well for almost all applications. Case 4: In ...
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Receive Mode Pending RF ...
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API Transmit Packet is ...
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’ When both API Send Data Complete and API Receive Packet are enabled, the Send Data Complete will be received before the transceiver sees the Receive API Packet. ...
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... Refer to the following sections to ensure that the OEM Host data rate matches the serial interface baud rate The AC4790 is a TTL device which can be interfaced to a compatible UART (microcontroller) or level translator to allow connection to serial devices. UART stands for Universal Asynchronous Receiver Transmitter and its main function is to transmit or receive serial data. ...
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Note: Enabling parity cuts throughput and the interface buffer in half The OEM Host Data Rate is the rate with which the OEM Host and ...
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BaudL Baud Rate (0x42) 115,200 0xFE 1 57,600 0xFC 38,400 0xFA 28,800 19,200 14,400 9,600 0xE8 4800 0xD0 2400 0xA0 1200 1. 57,600 ...
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... CTS When Half Duplex communication is chosen, the AC4790 will send a packet out over the RF whenever it can. This can cause packets sent by multiple transceivers at the same time to collide with each other over the RF. To prevent this, Full Duplex communication can be chosen. Full Duplex shares the bandwidth intelligently to enable two-way collision- free communication without any collision. This is done by calculating the amount of time until the next hop to ensure that it has time to send the packet ...
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... EEPROM. As the number of retries increases, the system latency will increase also When operating as shown below, an AC4790 transceiver is capable of achieving the listed throughput. However, in the presence of interference or at longer ranges, the transceiver may be unable to meet the specified throughput. RF Status ...
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... Channel Set 0 (AC4790 - 1x1 AC4790 - 200) 1 (AC4790 - 1x1 AC4790 - 1000) 2 (AC4790 - 1x1 AC4790 - 200 AC4790 - 1000) 1. All Channels in a Channel Set use the same frequencies in a different order. DES (Data Encryption Standard) - DES (Data Encryption Standard) – Encryption is the process of encoding an information bit stream to secure the data content ...
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... Max Power provides a means for controlling the RF output power of the AC4790. Output power and current consumption can vary by as much as ±10% per transceiver for a particular Max Power setting. Contact Laird Technology for assistance in adjusting Max Power ’ The max power is set during Production and may vary slightly from one transceiver to another. ...
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... RTS (if enabled The AC4790 has an interface buffer size of 256 bytes. If the buffer fills up and more bytes are sent to the transceiver before the buffer can be emptied, data loss will occur. The transceiver prevents this loss by asserting CTS High as the buffer fills up and taking CTS Low as the buffer is emptied. CTS On and CTS Off control the operation of CTS. CTS On specifies the amount of bytes that must be in the buffer for CTS to be disabled (logic High) ...
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prevent the transceiver from sending it data by disabling RTS (logic High). Once RTS is enabled (logic Low), the transceiver can ...
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... UP_Reset provides a direct connection to the reset pin on the AC4790 microprocessor and is used to force a soft reset. For a valid reset, reset must be asserted High for a minimum of 10ms When logic High, the transceiver interprets incoming OEM Host data as transmit data to be sent to other transceivers and their OEM Hosts ...
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... Configuration The AT Command mode implemented in the AC4790 creates a virtual version of the Command/Data pin. The “Enter AT Command Mode” Command asserts this virtual pin Low (to signify Command Mode) and the “Exit AT Command Mode” Command asserts this virtual pin High (to signify Data). Once this pin has been asserted Low, all On-the-Fly CC Commands documented in the manual are supported ...
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... The AC4790 transceiver contains static memory that holds many of the parameters that control the transceiver operation. Using the “CC” command set allows many of these parameters to be changed during system operation. Because the memory these commands affect is static, when the transceiver is reset, these parameters will revert back to the settings stored in the EEPROM ...
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Command Name AT Enter 0x41 Command Mode Exit AT Command Mode 0xCC Status Request 0xCC Change Channel 0xCC ...
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Prior to sending this command, ...
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The ...
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The OEM Host issues this command to read the state of both digital input lines ...
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The OEM Host issues this command to read any of the three ...
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EE PROM Byte Re ad Upon receiving this command, a transceiver will respond with the desired data from the addresses requested by the OEM Host. EE PROM Byte Upon receiving this command, a transceiver will write ...
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EEPROM P ARAMETERS The OEM Host can program various parameters that are stored in EEPROM which become active after a power-on reset. The table below gives the locations and descriptions of the parameters that can be read/written by the OEM ...
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EEPROM Length Parameter Address (Bytes) 0x56 1 Control 1 0x58 1 Interface Timeout 0x5B 1 RF ...
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EEPROM Parameter Address 0x90 Product ID 0xC1 API Control 0xC2 Protocol Status 0xC4 Session Count Refresh 0xC3 Random Back-Off 0xC8 Sense Adjust ...
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EEPROM Length Parameter Address (Bytes) 0xC9 1 Probe Report 0xD0 7 DES Key Range Default Description ...
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... D IMENSIONS Interface Connector - 20 pin OEM Interface connector (Molex 87759-0030, mates with Samtec SMM-110-02-S-D MMCX Jack - Antenna Connector (Johnson Components 135-3711-822)AC4790 (with MMCX connector) Mechanical www.lairdtech.com\wireless 8 ...
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... AC4790-1X1 0.200 005068004503 0.000 0.100 typ. Notes: 1) VCC must not exceed +3.3V DC. 2) This G ND pin to be used for RF ground. 3) Operating temperature -40C to +80C 3) Storage temperature -60C to +140C ...
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... Use several large vias (0.030" hole) to tie top side ground to the bottom layer ground plane. Note: Must provide solid copper Ground plane on the bottom side of pc board in this area. PN: AC4790X-1X1 SN: 005068004503 PCB THickness Notes: For 0.062 thick PC board microstrip width and spacing is 0.110 inches. ...
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... All of the above part numbers can be ordered as a development kit by prefacing the part number with “SDK-” example, part number AC4790-200A can be ordered as a development kit using the part number: SDK-AC4790-200A. All developer’s kits include (2) transceivers, (2) development boards, (2) 7.5 VDC unregulated power supplies, (2) serial cables, (2) USB cables, (2) antennas, configuration/testing software and integration engineering support ...
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... I OMPLIANCY NFORMATION Due to the RF antenna trace residing on the OEM Host PCB, the FCC will not grant modular approval for the AC4790- 1x1 and requires the OEM to submit their completed design for approval. Contact Laird Technology for the approval procedure Agency compliancy is a very important requirement for any product development. Laird Technology has obtained modular approval for its products so the OEM only has to meet a few requirements to be eligible to use that approval ...
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... Ankles, feet, wrists, and hands are permitted to be within 2 the antenna even if the equipment is designated as being greater than 2.5 cm). The AC4790 is not agency approved for portable applications. The OEM is required to have additional testing performed to receive this classification. Contact Laird Technology for more details. ...
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Label and text information should size of type large enough to be readily legible, consistent with the dimensions of the equipment and the label. However, the type size for the text is not required to be larger ...
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PPENDIX AMPLE Below is a simple switching power supply that provides enough current to easily power any Laird Technology OEM module. It utilizes low cost, off the shelf components that fit into a small area. This ...
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... All inputs on the AC4790-200 & AC4790-1000 are weakly pulled high via 10 kohm resistors. The AC4790-200 has 5V inputs while the AC4790-1000 & AC4790-1x1 have 3.3V inputs. The AC4790-200 uses an octal buffer to drop the 5V to the required 3.3V level; the -1000 and -1x1 leave this to the OEM. ...
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... III - API PPENDIX The API feature set of the AC4790 provides powerful packet routing capabilities to the OEM Host. The number of API configurations is endless as individual radios can all be configured differently to suit the OEM Host’s varying needs. Some of the most common implementations are described in the following pages. ...
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poll radio 1, the SAP transmits the packet using the following format poll radio 2, the SAP ...
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The remote response is dependent on the OEM’s specific needs and equipment. In many cases, remote radios are connected to dumb devices without ...
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Receive API is not enabled, the transceiver will receive the reply data only ...
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Radio B receives the packet “FIND D”, and stores it in the buffer until the current session with Radio 2 A has ended. ...
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A and radios B & C. When the repeater receives a packet from radio A, it will transmit the packet out to radios B & the repeater is set to Broadcast mode, radio A will receive a ...
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API T PPENDIX IMING IAGRAMS Session Count = 8, Retries = 3 Session Count = 3, Retries = 3 www.lairdtech.com\wireless IV ...
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Session Count = 2, Retries = 2 Session Count = 1, Retries ...