The only safe version of Ramps-FD is the V2.A, issued in February 2014. Former versions present high safety risks which were solved by the V2 issue. Unfortunately, The only Ramps-FD available on the market is yet (february 2016) on revision 1.2, while its manufacturer was repeatedly advised that the only safe version is the 2.A. Beware of confusing wording and absence of clear board revision mention from sellers. So, till the issue of a 2.A version, the Ramps-FD board shall be avoided. If you buy one, its better destination is a shelf for component reuse or a bin if you don't have the knowledge or will to modify it. This was discussed notably in following threads :
RAMPS For Arduino Due
RAMPS-FD v1.A is now in beta!
Arduino Due is the new Arduino board that is using an ARM Cortex M3 CPU. The Atmel SAM3X8E chip used on the Due operates at 3.3V and is not compatible with 5V. Therefore the RAMPS shield will not work with Due, and worse applying 5V to the Due's inputs will likely damage the chip. Therefore there are several possibilities: create a new RAMPS variant which is compatible with the Due. Possibly could also be made backwards compatible with Mega. create a RAMPS Interface Board (RIB) to sit between Due and RAMPS to perform level-shifting, and any other needed functions.
Why should i use Ramps-FD instead of Ramps1.4
Compare Ramps-FD with Ramps1.4,the Improvements of Ramps-FD are:
- The RAMPS-FD has other hardware protection, through the jumper cap control motor drive IC
- The RAMPS-FD Much more than Ramps1.4 2-way PWM
- The RAMPS-FD has Larger driving power than Ramps1.4
- The RAMPS-FD 'POWER has two choices：12v and 24v
why should I select Arduino Due instead of Arduino Mega?
- Due has lower power consumption, computes faster, and has much more storage than the ATmega2560
- CPU operates at 3.3V
- High-current IO pins are capable of 15 mA source, 9 mA sink
- Low-current IO pins capable of 3 mA source, 6 mA sink
- CPU package has an absolute max of 130mA
- The Due has 1 dedicated SPI port, and 4 multipurpose USART/SPI ports. The SPI port is only routed to the 6 pin header used for ICSP on Mega, but this is not used for ICSP on Due.
- The Due does not have any EEPROM
- MOSFETs need to be compatible with threshold voltage of 3.3V or better have a gate driver which allows any MOSFET to be used
- Expansion pins need to be level-translated, but this depends on how they are used
- Add ons: SD card, thermocouple drivers, LCD boards
- Is heat dissipation of Due ok with RAMPS shield over it?
- Yes, the Due consumes approximately 130mA. Also the ARM MCU get barely warm to the touch.
- Some opto-endstops need 5V power, and return 5V on signal
- (AUX-3) The SPI pins on the Mega (mapped to pins D50-52) are not SPI pins on Due
Hardware features known to be compatible
- The Allegro stepper drivers will run with VDD = 3.3V and the logic signals compatible with 3.3V. This should apply to all the Pololu style drivers.
- Servos "should" be able to operate with +5V power and a PWM signal of 3.3V
- Thermistors will operate at 3.3V but the Analog Ref is also 3.3V, so no changes should be necessary
- Mechanical endstops should be OK, if they do not use external pullup to 5V
Source files are hosted at github.
(The Arduino Due is based on a 84 MHz Atmel SAM3X8E 32-bit ARM Cortex-M3 CPU with USB OTG).
SAM3X8E Datasheet: SAM3X8E Product page