topic How to controll results? in Kinetis Design Studio

How to controll results?

piergiusepperan — Wed, 28 Oct 2015 16:19:26 GMT

Hi, I have to compute some values like current and resistance by software. I mean, I set a particular voltage from 0V to 3.3V ( so from 0 to 65534, for 16 bit) by software on a Digital to Analog Converter, then I want to compute the current, so I define the resistance (for example for 1 ohm resistance, I will write R= 19858, considering 16 bit, i Don't know if it is right) and then I compute the current I= voltage/R; Now, first of all, I don't know if it is possible to compute the current in this way, please, let me know how can I do. The second problem is that I want to verify this result, I mean, i want to veify if the current is right and I want to see the value of I (the current), on arduino I used the serial port and I wrote printf ("current", I); and i could see the result, is there a way to see the results on KDS? Thank you

Re: How to controll results?

ZhangJennie — Tue, 03 Nov 2015 06:56:06 GMT

Hi,

i think your solution of calculating current is OK.

regarding how to see result with KDS, i suggest you use printf. here is an article for this topic,

How to use printf() to print string to Console and UART in KDS2.0

can this help you?

Have a great day,
Zhang Jun

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Re: How to controll results?

petertoenz — Thu, 05 Nov 2015 10:02:28 GMT

Hello

Your calculation is a bit confusing (for me)

Here ist my way to solve that problem (if you can use float-values):

float R = 1; // [Ohm]

int16_t U_raw = acd_get_result(); // replace with your function

float U = (float)U_raw * ( 3.3 / 2^16 ); // [Volt] (or replace (3.3/2^16) with 0.00005)

float I = U / R; // [Ampere]

Peter

Re: How to controll results?

piergiusepperan — Thu, 05 Nov 2015 17:12:52 GMT

Thank you Peter, I already did like you sugested and It works.