To prove this point look at how many Arduino projects contain a delay(x00) in the loop; so if things go to slow simply decrease this number to release some CPU cycles ;-). My motor controller has 4 pins that give a 0-5V output depending on the current the 4 motors draw (5V = 5A). That is, the double implementation is exactly the same as the float… Arduino CNC Shield – 100% GRBL Compatable; Programming hundreds of Arduino Minions in one go; Can-Bus Breakout (Picking Can Bus over RS485) DIY Robot Arm by UFactory; Arduino Web Dashboard without the need of web-server; Arduino Float to String (That actually works) SparqEE CELLv1.0: Cellular made easy (Arduino/Pi/+) Float and double are the same on AVRs - they aren't on the Due and some other fancier microcontrollers, but they are for AVRs. Eighteen Hints to Reduce Code Size 1. 2. 4. I've searched Arduino.cc, the forum, googled it and can't find anything. I must verify my math among other things. Use unsigned if applicable. Compile with full size optimization. If a non-local variable is only referenced within one function, it should be declared static. So I wrote some code to sent the values to the serial monitor and I'm having some problems. Float has size of 4 bytes. I have a float variable with a value like -99,9 ... Debian,Mint,Ubuntu Arduino Mega 2560 Arduino Nano Arduino Duemilanove MAC OS Montain Lion Raspberry PI Model B. AWOL Guest; Re: Serial.write a float value #1 Jul 02, 2012, 06:45 pm. Collect non-local data in structures whenever natural. I could probably modify it if I just knew where 'rounding' is located. Therefore you need 4 bytes in your array to store each float. On the Arduino Due and SAMD based boards (like MKR1000 and Zero), an int stores a 32-bit (4-byte) value. float is CPU/RAM intensive IMHO In many Arduino projects there is plenty of CPU/RAM left so I don't think this is a real issue. Make an Arduino Sketch Smaller: If you've every hit that 32,256 byte maximum on an Arduino Uno and wondered if you could make your sketch smaller instead of upgrading to a Mega, this is for you! float introduces a rounding problem. ... An example can be found in one of the DHT22 sensor libraries to disable the code that returns float values. This yields a range of -32,768 to 32,767 (minimum value of -2^15 and a maximum value of (2^15) - 1). On the Arduino Uno (and other ATmega based boards) an int stores a 16-bit (2-byte) value. The reason that Serial.print(float) is able to print the floating point is because Arduino painfully and tediously implemented the Serial.print() function (the source code can be viewed at ArduinoCore-avr github page, it is almost like a hack) to support the floating point print. I assume it is rounding. Use local variables whenever possible. On the Uno and other ATMEGA based boards, this occupies 4 bytes. 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