B&B Electronics RS-485 manual

485SDA103798 Manual Cover Page B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 RS-485 Data Acquisition Module Model 485SDA10 Document No. 485SDA103798 This product Designed and Manufactured In Ottawa, Illinois USA of domestic and imported parts by B&B Electronics Mfg. Co. Inc. 7[...]

485SDA103798 Manual Table of Contents i B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Table of Contents Chapter 1- Introduction ........................................... 1 485SDA10 Features ...................................................... 1 Packing List ...................[...]

ii Table of Contents 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Set Turn-around Delay Command ............................... 17 Read Module Configuration Command ........................ 17 Chapter 4 - A/D ...................................................[...]

485SDA103798 Manual Table of Contents iii B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 TABLE 5.1 - DIGITAL I/O MASK VALUES .................................... 24 TABLE A-1 EXTENDED COMMANDS ........................................ A- 2 TABLE C-1: DECIMAL TO HEX TO ASCII TABLE ..[...]

485SDA103798 Manual 1 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Chapter 1- Introduction 485SDA10 Features The 485SDA10 is a general purpose control module which operates through an RS-485 interface. The 485SDA10 offers 11 channels of 10-bit A/D (analog to digital), 3 digital in[...]

2 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Figure 1.2 - General Block Diagram Packing List Examine the shipping carton and contents for physical damage. The following items should be in the shipping carton: • 485SDA10 unit • One 485SDA10 3.5” disk ?[...]

485SDA103798 Manual 3 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Windows 3.11 1. Insert SDA Logger installation disk in your floppy drive. 2. Click the File Manager button. 3. Select the floppy drive containing the SDA Logger installation disk. 4. Double click the Setup.exe icon[...]

4 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 variable resistor must be greater than 1k Ohms to limit the output current to 5mA. • Connect A/D Ref Input+ to +5V DC. • Connect A/D Ref Input- to analog ground (See Figure 1.3). • Connect the 485SDA10 to an[...]

485SDA103798 Manual 5 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 485SDA10 Specifications Analog to Digital Converter Resolution: 10 bit Channels: 11 Reference Range: 5.0V DC max. (4.888 mV per bit) 2.5V DC min. (2.444 mV per bit) A/D Ref. Input - 0V DC to 2.5V DC A/D Ref. Input [...]

6 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Chapter 2 - Connections This chapter will cover the connections required for the 485SDA10. There are four sets of connections: • A/D converter • Digital I/O • Serial port • Power supply Do not make any con[...]

485SDA103798 Manual 7 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 A/D Ref Input - T he voltage connected to this pin determines the low end of the input voltage range. For proper operation, this pin must be connected to a DC voltage between 0 and +2.5 Volts. Typically, this is co[...]

8 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Digital I/O Connections The digital I/O connectio ns are made on the I/O port, which is a DB-25S (female) connector. Table 2.1 shows the pinout of the I/O port. The next sections explain the functions and connecti[...]

485SDA103798 Manual 9 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Digital Ground Connect the digital ground pin to your digital device's ground. To minimize noise, do not connect analog ground and digital ground together. Connect unused digital inputs to digital ground. Typi[...]

10 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Serial Port Connections To communicate with the 485SDA10 module, it must be connected to an RS-422/RS-485 serial port. The 485SDA10 works with 2-wire or 4-wire RS-485. The unit automatically detects baud rates fr[...]

485SDA103798 Manual 11 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Power Supply Connections The 485SDA10 requires 7 to 18 V DC at 30mA. Remember that the 30mA requirement doesn’t include the power consumption of any external devices. Therefore, any current sourced with the digi[...]

12 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Chapter 3 - Commands There are only three commands required to control the 485SDA10: • Read A/D command • Read digital I/O command • Set output states command There are four commands used to configure the m[...]

485SDA103798 Manual 13 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 The decimal and hexadecimal equivalents of some ASCII characters are shown in Table 3.2. Notice that the ASCII representation of the character “0” does not have a value of 0. Refer to Appendix C for more ASCII[...]

14 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 The Read A/D channels command returns two bytes for each channel read. The two bytes represent the most significant byte (MSB) and least significant byte (LSB) of the reading. The MSB is received first, followed [...]

485SDA103798 Manual 15 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Reading Digital I/O Command The Read Digital I/O command returns a byte which represents the states of the 3 digital input and 3 digital output states. Bits 3-5 correspond to the states of digital inputs 0-2. Bits[...]

16 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Set Digital Output Command The Set Digital Output command is used to set the states of the 3 digital output lines. This command requires a data byte. The data byte is used to specify the output states. Bits 0-2 c[...]

485SDA103798 Manual 17 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Set Power-up States Command The Set Power-up States command is used to set the st ates of the digital outputs at power-up. This command requires a data byte. The data byte is used to specify the power-up output st[...]

18 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 { address}{ states}{ delay} Where {address} is a byte representing the module’s current address, {states} is a byte representing the module’s power-up states, and {delay} is a byte representing the module’s[...]

485SDA103798 Manual 19 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Chapter 4 - A/D This chapter will deal with manipulating an A/D reading and cover some of the aspects that were not explained in the A/D Connections chapter. Sampling Rate The A/D converter has a conversion time o[...]

20 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Data Range The data range of the A/D converter is determined by A/D Ref Input+ and A/D Ref Input- . A/D Ref Input- sets the bottom of the data range. Any input voltage that is less than or equal to the A/D Ref In[...]

485SDA103798 Manual 21 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 The step size is also referred to as the resolution. Once the step size is known, all that is needed to determine the voltage of an A/D input is the number of steps. The data returned from the 485SDA10 is the numb[...]

22 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Chapter 5 - Software This chapter covers programming techniques such as constructing a command string, receiving data and manipulating data. The various steps and examples are shown in QuickBasic. If you are prog[...]

485SDA103798 Manual 23 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 ‘Get the value of channel 1 MSB$ = INPUT$ (1, #1) LSB$ = INPUT$ (1, #1) reading1 = (ASC(MSB$) * 256) + ASC(LSB$) ‘Get the value of channel 0 MSB$ = INPUT$ (1, #1) LSB$ = INPUT$ (1, #1) reading0 = (ASC(MSB$) * [...]

24 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Table 5.1 - Digital I/O Mask Values Example 5.2 - Determining the status of Digital Input #1 of the module with and address of 10. mask = &H10 Command$ = “!” + CHR$( addr) + “RD” Print #1, Command$; R[...]

485SDA103798 Manual 25 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 b) Set Appropriate Outputs LO W states = states AND (NOT(mask)) By “ ANDing” the current states with the complement of the appropriate mask of a digital output (given in Table 5.1), the output’s data bit wil[...]

26 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Example 5.4 – Change the address of a model from 5 to 10. addr = 5 newaddr = 10 Command$ = “!” + CHR$( addr) + “SA” + CHR$( newaddr) Print #1, Command$ Set Power-up States Command The Set Power-up State[...]

485SDA103798 Manual 27 B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 ‘ Clear bit 2 of states to make digital output 2 LO W states = states AND (NOT(4)) Command$ = “!” + CHR$( addr) + “SS” + CHR$(states) Print #1, Command$ At power-up digital output 0 will be HIGH, digital[...]

28 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Read Module Configuration The Read Module Configuration command reads the 485SDA10’s address first, then the power-up states, and finally the turn-around delay. The steps to reading a module’s configuration a[...]

485SDA103798 Manual Appendix A A- 1 B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Appendix A: Adding Data Field Confirmation W ith serial communications in a laboratory environment, the possibility of a communication error occurring is minimal. However, in a harsh or an industrial[...]

A- 2 Appendix A 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Where “x” is the required data byte and “~” signifies the complement of the specified byte. Table A-1 Extended Commands Function Command Response Read A/D Channels #{ addr}RA{x}{~x} { chxmsb}[...]

485SDA103798 Manual Appendix B B- 1 B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Appendix B: Analog Input Impedance When interfacing with an A/D converter, it is important that the device you are connecting can drive the A/D input. To determine if your device can drive an A/D inp[...]

B- 2 Appendix B 485SDA103798 Manual B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Simplified Analog Input Analysis Using the equivalent circuit in Figure B-1, the time required to charge the analog input capacitance from 0 to Vs within ½ LSB can be derived as follows: The capacit[...]

485SDA103798 Manual Appendix B B- 3 B&B Electronics - - 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Figure B-1. Equivalent Input Circuit Including the Driving Source[...]

485SDA103798 Manual Appendix C C- 1 B&B Electronics - - PO Box 1040 -- Ottawa, IL 61350 PH (815) 433-5100 - - FAX (815) 434-7094 Appendix C: Decimal to HEX to ASCII Table Table C-1: Decimal to HEX to ASCII Table DECIMAL to HEX to ASCII CONVERSION TABLE DEC HEX ASCII KEY DEC HEX ASCII DEC HEX ASCII DEC HEX ASCII 0 0 NUL ctrl @ 32 20 SP 64 40 @ 9[...]

FCC Class A Equipm ent Stat ement FEDERA L COMM UNI CA TIONS COMM ISSION RA DIO FREQ UENCY I NTERFA CE STA T EMENT Class A Equipmen t This equipm ent has been tested and f ound to com ply with the limits for Clas s A digital device, pursuant to Par t 15 of the FCC Rules. T hese limits are designed to provide reas onable protection against harm ful [...]