I have been building up the second CRAMPS board to verify the low-cost PCBs from off-shore really work as expected. Since I'm doing another build anyway, I have been documenting the process with pictures and have created a CRAMPS 1.0 page with assembly details, ECOs, and other board details on the RepRap Wiki. Follow along there if you're interested in tracking progress or are building your own board. If you are interested in building up a board and can hand-solder the six fine-pitch SMT parts, send me an email and I'll try to get you a bare PCB.
Meanwhile, work is progressing on the next version of the CRAMPS board thanks to Murry Lindeblom. Murry has been doing some great with KiCAD getting the schematic whipped into shape while I've been busy with other projects. The main changes are to simplify the design, reducing parts count and making the board cheaper to produce. See the list of ECOs on the RepRap Wiki for hints about the next version.
Hey Charles, I didn't quite understand the ECO on the regulator - Clearly if you're running from 12V you don't need a regulator, but what if you do want to run from 24V? In my couple of printers I have completely switched to 24V as it does everything better, from heating cartridges and beds faster to tightening up motor movement and eliminating missed steps on direct drive extruder. Will the next version be capable of running on 24V without the regulator?
ReplyDeleteThe board works fine on 24V, I prefer using 24V as well. The only thing you may have issues with running on 24V is the two "medium currnet" Aux FET outputs (FET 5 and 6). These FETs are intended to switch 5-12V, and if you need to use these outputs you will need to supply a power source <= 12V for these two outputs. Everything else, including the motor drivers and high-current heater FET outputs work fine with 24V.
DeleteThe board works fine on 24V, I prefer using 24V as well. The only thing you may have issues with running on 24V is the two "medium currnet" Aux FET outputs (FET 5 and 6). These FETs are intended to switch 5-12V, and if you need to use these outputs you will need to supply a power source <= 12V for these two outputs. Everything else, including the motor drivers and high-current heater FET outputs work fine with 24V.
DeleteHi Charles, was there any specific reason you picked the specific pinouts and GPIO pins? I'm looking at your schematics and you have X-MIN,Y-MIN,X_DIR,Y_DIR on P8/B, and then you have X-MAX,Y-MAX (makes sense so far), FET1 (why was this inserted here), X_STEP, Y_STEP (the steps pins are now 1 off from the DIR pins). Was there any specific reason to put in the FET1 between the ?-MAX adn the ?_STEP pins?
ReplyDeleteThe existing software uses GPIO pins for step/dir and PWM, so doesn't much care about pin assignments. I generally tried to assign the pins to route well on the PCB, while assigning things like hardware PWM pins to either the FET outputs or the step pins. Some pins were also placed with concern to their default state (pulled high or low). Mostly, I was just trying to cram everything in without needing to disable HDMI or eMMC!
ReplyDeleteAhh... so it is just ease of routing and default states. Your pinouts are somewhat close to the BeBoPr Bridge pinouts. I'm wondering if there it is worth trying to be pin compatible with them or not. The reason I'm looking into this is because I'm attempting to design a stepper cape as well, but the controllers built in instead of using the Pololu carriers. I'm also simplifying the design because my focus is more towards a low cost ShapeOko 2 driver (I just bought one), as well as for general purpose robotics (so I don't need the FETs and the ADC). I'm also trying to make it stackable. I'm just wondering if I should try to be pin compatible with your CRAMPS board (btw, do you mind if I sell your CRAMPS board as well on my webstore? I can offer you a percentage royalty on the sales).
DeleteI wasn't worried about being exactly pin-compatible with the BeBoPr because there are more axis on the CRAMPS board.
DeleteThe design is open, so you (or anyone else) can sell them if you want. Nothing would make me happier, I don't want to get into the board making business. Note that there is an updated version being worked on which will be somewhat simpler, but the current version works fine. Let me know (via email) if you need any help with the design.
Hi Charles, I bought a couple CRAMPS boards through Oshpark, and am now looking to build them up. Should I use the CRAMPS-BOM.xls or CRAMPS-BOM-v1.1.xlsx from github? I haven't looked at them closely, so not sure how different they are.
ReplyDeleteThanks.
Do not use the v1.1, that's for the new board. Use the CRAMPS-BOM.xls file, but double-check with the RepRap wiki page for the 1.0 board. There have been some ECOs, mostly leaving some parts off but I changed the thermistor pull-up resistor as well:
ReplyDeletehttp://reprap.org/wiki/CRAMPS1.0
I'm about to start a 3D printer project and I'm wondering if I should wait for CRAMPS1.1? I still have to wait for BBBs to start shipping again, so I still have to wait for other things.
ReplyDeleteI'm planning to build a DLP type 3D printer, so it wont have demanding motion control, but I also wanted to try replacing the projector with a UV laser and a galvonometer to deflect the beam - these take analog inputs. Originally I was planning on building a cape just for this, but CRAMPS + my own DAC module connected to AUX3 seems to be a perfect fit.
Frank
That is, using the SPI on AUX3.
DeleteI can't tell you if you should wait or not. What I can tell you is that it will probably take me about 2-3 weeks to get the PCB design finished, then another 2 weeks or so to actually get back blank circuit boards.
DeleteIt depends on your time frame, how well the new CRAMPS design fits with what you want vs. other available boards, and whether you want to build something yourself or buy a ready-to-run board.