A non-volatile storage is useful for storing config or board identification to allow single firmware for different shield versions.

For compatibility with RADDS, use 24LC256 type on I2C-0. Compatible with 3.3V or 5V base board.

There are some odd tracks under some of the resistor packs that could be cleaned up.

Unscrupulous vendors making the board may not mask the component properly, leaving the tracks bare/tinned, which could lead to shorts under the already small Resistor Packs.

Also related to Bug #7

Note: While larger resistor packs would be nice, no investigation has yet been done to identify a suitable component with a viable footprint that can be used. This bug therefore takes priority to Bug #7, especially as it's fairly easy to resolve.

Hi Bob,

Since you've asked me about my LPCXpresso before, I'll take that as permission to make suggestions. I just wanted to let you know that there is a small issue on the board due to poor documentation of the LPCXpresso. Currently you have jumpers to select various 5V lines to go into the LPC_VIN pin. Unfortunately, that pin is not used on the "main" side of the LPCXpresso. That pin simply connects to the LPC-Link (the attached debugger) which sends 3.3V back. So if you remove the debugger the LPC_VIN pin is no longer attached to anything since there's no on-board regulator, and the board can powered only by putting 3.3V on the LPC_3V3 pin.

Whoever wrote the LPCXpresso datasheets should be soundly beaten for not making this clear--I spend a good three days thinking my board was a dud, and I am surely not the first to fail to understand this.

Can we implement thermistor protection, as has been implemented in RAMBo v1.2? Given that the circuitry was based on the thread that bobc/nophead & myself all participated in, I don't see any reason we can't also adopt it.

RAMBo PDF of the schematic (showing the protection circuitry in the section marked "Thermistors") can be found on github at https://github.com/ultimachine/RAMBo/blob/master/docs/images/RAMBoSchem.pdf

Note: The OVRef in that design is 4.7V (using a 4.7V zener), whereas it may need to be ~3V with a Due. This would definitely lead to a compatibility difference when trying to use the same shield on either the Due or Mega, though not one that should be too much of a problem to work around.

Can we move Q201 slightly further away from F101 (towards the other FETs)?

At the moment there is no room for a heatsink should you need one, without the heatsink touching the fuse holder body or by bending the component legs (toward the other FETs). No other components need to be shifted, as the space available between Q201 and Q501 should be sufficient

It would like to be built up one 3d printer using your panel (REMPS-FD) this will be the third machine what I prepare. Unfortunately home manufacturing too thin the lines on the mucus sheet. I can buy an empty pcb from you possibly, or a full-fledged one?
I'm sorry, but my English not the best one.
Thanks
Istvan

If the Due is not powered but RAMPS-FD is, then the heater outputs (D8-D11) default to an on state.

Redesign FET control circuit to ensure that heater outputs are not active is Due is not powered.

Change the 10uF electrolytics caps used on the ADC filters for ceramic.

Hello,

I'm trying to do the RAMPS FD board for myself from scratch, and I encountered incompatibilities in the files. e.g the diagram has 220 ohm resistors that are not in the BOM. Please inform me if schematic and garber are correct and only BOM is not complete?

I already have a ready board and I do not know whether to solder it.

Best regards

I have S109 drivers based on TB67S109AFTG. They need vcc=5V.
May I set VLOG JP101 to 3-2, (FD_5V) with Due ?

Consider adding connector for micro-SD card. SD card can be used for storing config and data files.

uSD can be interfaced directly to Due, but will need level conversion for Mega.

Since an SD card can be easily added with SDRAMPS, it is not essential to have onboard.

Action: defer for now and review later, there may be more important things to add.

The tracks around the hole near Pin 21 are a little close to the hole edge.

In theory, this could cause issues with mounting, or issues with operation if the board maker makes the holes just a little too large, damaging the tracks.

Would it be possible to use a slightly larger size resistor pack?

They're very finicky to solder into place if you're doing a one-off run, and even with paste/oven, bridging between the pins is a common occurrence.

Specifically around:
Pins between +5V and VIN
Thermistors and End Stops.

U3 (12V regulator) bumps into C101.

It looks like we make some more space by moving R202, P203, JP102, C102 and C207 further to the right (away from the power/heated bed connectors), so that U3 can then be moved away from C101.

Note: We want as much space between C101 and U3 as possible, so that if required, you can put a heatsink on U3.

I am interested in making an RIB, and I noticed a small issue. The pins right above 22 and 23 (Pins 1 and 2 on P4 on the schematic) are 5V on both the Mega and the Due. The schematic shows it as being 3.3V on the Due, which it is not (reference: http://arduino.cc/forum/index.php?PHPSESSID=3a01035c9ec06f894820c1b63cd9fa23&/topic,132130.0.html).

There appear to be two problems:

1. AREF is an input to Due, not an output, and it is not connected
   Fix is to revert to 3.3V as reference voltage, as previous revision.
2. The OVREF voltage is too low at about 2.35V. The resistors R1002, R1003 and R1004 result in a reference of about 0.9V on U1001.
   Values of 6k8, 1k8 and 1k should give better output, approx 3.125V.

The default state for GPIO pins leaves these outputs turned on.

Add 10k pulldown resistors to prevent accidental turn on.

Hi,
I'm Yasuo Suto.
I'll try to use RAMPS-FD for delta type 3D printer.
So, my mechanic colleague request the DXF file of RAMPS-FD in order to design the box of the board set (Aruduino due + RAMPS-FD).
I had gotten the garbar data, but I don't have DXF exchage tool which this garber data format.
If you have DXF file, please send it to me or upload the site.
My e-mail address is below.
[email protected]

Best regards,
Yas

as per subject would it make sense to update Ramps FD ? are there any improvements that could be made?

5V is provided by the Due, but is limited to 800mA (or less). This is not really enough for extras like LCD, SD, servos, expansion boards. RAMPS has a seperate 5V input for servos.

Need to look at providing 5V regulator on board, or at least input for external 5V (may require yet another jumper?).

It would be really nice to run off a 5V standby (ATX PSU), but I don't think 5V can be back fed safely to the Due.

When running @24v with JP102 -VSEL pins 1-2 selected I found that the 7812 is getting very hot. I could actually smell it even with a fan running. I believe this would be a fairly typical problem when trying to drop 12v over a linear regulator like this one. I know there are a number of workarounds and personally I replaced mine with a cheap buck converter (LM2596). I can see it is still spec'd so I thought maybe you could investigate some alternatives. Myself I wouldn't mind a separate input for board power / hotend & fans and then just supply my own power (I did briefly feed 12v in via pin 2 of JP102 but it was a messy solution). It's probably not what most others would want but would make a nice option.

Replace the ESTOP 2 pin header with a locking connector like P901, P902 and P105.

I wouldn't want the ESTOP connector falling off during a job!

Note: I've populated mine with one already, but it sticks over the side <1mm. May require moving the connector slightly away from the edge of the board (room seems available).

Move the +5V pin on the endstop connectors 2.54mm further away from the Signal pin, creating a 4 pin connector, keyed with a gap (previously discussed).

This will stop people putting endstops that use both ground and 5V in back-to-front (eg: optos and hall-o's), and frying them. Also those people making their own boards using microswitches can leave out the 5V pins altogether (by enabling the pull-ups using JPB01).