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How do I make the math instruction and analog comparator block count up to the value 999999999

Created by: duma_calin145 at: 7/31/2025 10:55 AM (24 Replies)

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7/31/2025 10:55 AM	Rate (0)
duma_calin145 Joined: 7/24/2025 Last visit: 8/17/2025 Posts: 26 Rating: (0)	I made a program with 2 digital sensors, I1 and I2. The role of the project is for Sensor 1 to count my inputs and sensor 2 the outputs. I made the program like this: I connected I1 to the counter-Mathematics instruction1-Analog comparator then the sensor I2 connected to the Mathematics instruction 2 and in the analog comparator. On the display I see INPUT OUTPUT and LOST. The program works but if the INPUT sensor detects 751234 Inputs and I2 751230 outputs on lOST I have a value of 0. The question is, can I make the math instruction counters and analog comparator count over a value of 32k?

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7/31/2025 11:06 AM	Rate (0)
ixo65 Grandmaster Joined: 12/18/2014 Last visit: 9/1/2025 Posts: 35909 Rating: (4496)	This isn't possible because LOGO! only recognizes integer values (-32,768 to 32,767) for mathematical calculations. This applies to both the mathematical instruction and the analog comparator. In both cases, values above 32,767 are limited to 32,767.
	Last edited by: ixo65 at: 07/31/2025 11:07:02
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7/31/2025 11:17 AM	Rate (0)
duma_calin145 Joined: 7/24/2025 Last visit: 8/17/2025 Posts: 26 Rating: (0)	Hello ixo65 Thank you for your reply But is there another way I can use other blocks to compare the pulses I have from the sensors? I have a calculation with values over 32K Thank you
	Last edited by: duma_calin145 at: 07/31/2025 11:18:12
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7/31/2025 11:39 AM	Rate (0)
qwazee Platinum Member Joined: 3/30/2020 Last visit: 9/1/2025 Posts: 5414 Rating: (1063)	Do I understand your situation?
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7/31/2025 11:46 AM	Rate (0)
ixo65 Grandmaster Joined: 12/18/2014 Last visit: 9/1/2025 Posts: 35909 Rating: (4496)	qwazee Do I understand your situation? The up/down can only count to a maximum of 999,999. But the topic starter wants to compare values of 999,999,999.

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7/31/2025 11:51 AM	Rate (0)
duma_calin145 Joined: 7/24/2025 Last visit: 8/17/2025 Posts: 26 Rating: (0)	Hello qwazee thank you for your answer The logic of my code is: I1(Sensor) is connected to counter1, counter 1 is connected to math instruction and from math instruction is connected to analog comparator. I2 (sensor) 2 is connected to counter 2, counter 2 is connected to math instruction 2 and math instruction 2 is connected to analog comparator. The sensors are digital
	Last edited by: duma_calin145 at: 07/31/2025 11:51:40
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7/31/2025 11:57 AM	Rate (0)
duma_calin145 Joined: 7/24/2025 Last visit: 8/17/2025 Posts: 26 Rating: (0)	qwazee and ixo65 Yes exactly I want to compare the value 999,999,999

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7/31/2025 12:41 PM	Rate (0)
qwazee Platinum Member Joined: 3/30/2020 Last visit: 9/1/2025 Posts: 5414 Rating: (1063)	So.. you cascade the counters. Set the target of 0 to something like 100,000 which means the next counter counts in units of 100,000 units. Cascade so much as you want which still makes your display 'easy'.
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7/31/2025 1:00 PM	Rate (0)
duma_calin145 Joined: 7/24/2025 Last visit: 8/17/2025 Posts: 26 Rating: (0)	And the solution would be the following; For I1 (sensor) is connected to counter 1, counter 1 and to put another counter is connected to the math instruction, and the math instruction is connected to the analog comparator. I2 (sensor) 2 is connected to counter 2 and to put another counter, counter 2 is connected to math instruction 2, and math instruction 2 is connected to the analog comparator. So the solution would be: Should I put 2 counters in series? I have a code block but it won't let me load it Would that be okay?

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7/31/2025 1:07 PM	Rate (0)
qwazee Platinum Member Joined: 3/30/2020 Last visit: 9/1/2025 Posts: 5414 Rating: (1063)	You are repeating the same concept over and over. It does not bring clarity as to how you approach your problem. I do not share your thinking of using a math instruction. -- possibly because I do not follow your thinking clearly. Show us what you are planning. Whatever you want to share can be placed in a ZIP file and added to the post. You have to use the classic forum interface to have the "Add attachment" facility.
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