#LOGICWORKS 7 SEGMENT DISPLAY HOW TO#
#LOGICWORKS 7 SEGMENT DISPLAY DRIVER#

Pull out these 3 new extracted 1-digit strings for each digit, convert to a back to an integer number using the 'ACI' instruction, then run each integer number through the 7-Segment Decoder routine, then send the chosen Output Word to the PLC output module for that number position. Then use 3 versions of the RSLogix instruction AEX, with Indexes of 1 (0's digit), 2(10's digit), or 3(100's digit), and a Number setting = 1. I would probably save each new set of 3 digits as a String (use AIC to convert Integer to String).

#LOGICWORKS 7 SEGMENT DISPLAY HOW TO#

Still pondering how to extract the 10's and 100's digit. Your logic for these 7 outputs would look like this: (later). You should use OW8 Outputs 0 to 6 for your first 0's-place digit segments A to G. (You will need a module for EACH of you display digits, with one spare output per module, unless you want to get into complicated multiplexing). For example, suppose you assgin your first 0's place digit to your first 1794-OW8 module. For each Decimal Number, write PLC logic to produce the Segment Output. You can ignore the 'Segment IN' column and instead ONLY use the 'DECIMAL NUMBER' AND the 'SEGMENT OUTPUTS'. All you have to do is write logic for each set of 7 outputs, so they they work as shown in the Truth Table of my Post #5. For each digit, you will need 7 OW8 Outputs. Use ONE of your 1794-OW8 Outputs to turn ON/OFF ONE segment of 4 lamps. Each number of your display has 7 segments, but each segment is made up of four 24 VDC lamps.

#LOGICWORKS 7 SEGMENT DISPLAY DRIVER#

I am not firing a 7 segment display driver with BCD, I would like to fire them (each digit) with a 1794-ow8

To light up any digit, say '9', turn on bits that add up to a BCD 9 (inputs 3 and 0).įor a complete 3-digit decoder, you would need logic for each digit 0 to 9 for the 4 outputs for each digit (9 x 4) = up to 36 rung branches for each of your 3 digits, but some segments will not be lit for some digits so the total branches will be less. Your 4 inputs to each digit should be labeled the power of 2 for that position - 0,1,2,3 (because 2^0 =1, 2^1 = 2, 2^2 = 4, and 2^3 = 8).

My display is 3 digits old school 24 vdc lamps configured with 4 lamps per segment.It should have 7 lamps per segment, but only 4 inputs per those 7 segments, make 1 digit from 0 to 9. If Input 0 = '2', then turn on the segments needed to light up a '2', and so on for the 9 0-place digits. So for each number, figure out which segments have to be ON, then write rung logic: IF Input 0 is equal to '1', then OTE outputs for these segments 1 to 7 needed to light up a '1'. For each of your 3 digits, 'XXX' you can have segments lit to produce numbers 0 to 9 for each of the 3 digits. You need to write logic for a BCD to 7-segment Decoder.

Logicworks 7 segment display