برد کنترلر RAMPS-FD-RepRap - پرینتر سه بعدی اورجینال

نقد و بررسی اجمالی

برد کنترلر پرینتر۳D 32 بیتی Ramps-FD سازگار با آردوینو Due

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
Campare Ramps-FD with Ramps1.4,the Improvements of Ramps-FD are below
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 selectArduino Due instead of Arduino Mega
due has lower power ，computing faster and flash，sram bigger than mega2560
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

Hardware issues
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
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

:Add-on compatibility
Sdramps (AUX-3 SPI connector) This board has a 5->3.3 voltage regulator and a level translator. I think it will work and be compatible if powered from 5V, but will not work if powered at 3.3V, because the input to the regulator is too low

:Possible improvements
Move connectors near to board edge
Allow for latching or screw terminals

:Firmware changes
(Firmware needs to be compiled with ARM compiler (gcc
Arduino libraries may be compatible
Any references to AVR CPU peripherals, AVR include files or AVR compiler features need to be ported
There is no EEPROM on the SAM3X