Updating the Firmware

I've had enough of fiddling with bed leveling. It would be OK if the bed didn't sag in the middle. I have added some shims (just paper but they kind of work) but that isn't a good cure. I'm planning on using manual mesh leveling to do the job.

To that end, I found that I needed an Arduino UNO or nano which I don't have. I do have a couple of others but it doesn't look like they will do the job. The UNO isn't expensive but it's in China so I'll have to wait. In the mean time I know someone who has done this before and has a UNO that he is willing to lend me.

Update - 2019-Oct-14: I've got the firmware updated! Lots of research (I'm obsessive about this kind of thing) before I started paid off and it all went very smoothly. The only enhancement I added was manual mesh so I could overcome my warped bed - I've got about a 0.15 mm dip kind of in the middle. Yes, it isn't nicely symmetrical which should not come as a surprise. The manual mesh should be able to deal with this. I have not yet tried the manual mesh but I have done one print with the new firmware. One thing I noticed right away was something I noticed with the stock version - homing at the start of a print would move the X, Y, and Z directions one at a time in sequence. I figured that the X and Y could easily have been accomplished together. The new firmware actually does this. It's not a big thing but I'm glad somebody else thought this was a good idea and put it in the code. I also think that things are quieter although I don't have any to actually check this.

I tested the one thermal runaway check (no evidence of actually heating with power applied to the heating element) and it works perfectly. The test for this is to disconnect the heater at the board (you only need to remove one wire) and then trying to heat up the hot end.

There are various other interesting things in the firmware reflected on the display that I'm still exploring.

Update - 2019-Dec-24: I've been using manual mesh for a few weeks now and it has been solid. No more leveling issues! I've done the leveling procedure only twice (once after I added the PEI sheet) and have not needed to redo it since. It's great.