Gen7 V1.3.1 board with Marlin

Traumflug answering some of my questions again. I am using a gen7 V1.3.1 board with the temp sensor hack described here

Also, I am using the SevenSwitch to control a fan.


I cannot get Marlin to work. I got it to upload, but Pronterface
continually reports a brown out reset.

Brown out means, 5V supply goes below 4.3V. That's surprising, as the firmware has no direct influence on this. Is it actually such a reset or is it just Marlin doing a wild guess?

This never happened with
Teacup, but I assume has something to do with all of the extra
memory usage?

How big compiles Marlin these days? ATmega644's limit is at 64-2 = 62 kB. Also, RAM should be used up to some 80% to 90% only, as there has always to be room for the stack.

Stack is the space in memory where local variables and return-from-subroutine information is stored. It's adjusted dynamically at runtime and hard to guess how big exactly it can get.

Anyway I was wondering what bootloader you burned onto
the chip because I did not want to go through the effort of trying
to burn another bootloader if it is already the latest one.

Bootloader sources were adjusted to also support the 1284P, but this doesn't change the result for the 644(P).

Bootloader and firmware are entirely independent from each other, so a bootloader fault is unlikely as long as the firmware uploads.

However, unlike Teacup, Marlin uses Arduino libraries, which changed drastically between Arduino 0023 and Arduino 1.0. The newer library is worked into the Gen7 Arduino IDE Support 2.0 package, but I'm not sure which one works better. I guess Marlin people still work with Arduino 0023, so this, together with the older Gen7 Arduino IDE Support package, might be worth a try.

Also,
might there be some way to edit the Marlin firmware so that it does
not trigger the reset?

Obviously, the answer to this requires to find the reason for this reset, first. :-)

For me it's 46,856 bytes.
I tried this workaround, [github.com]
That got the motors working, but thermistors and heaters are completely dead. Even when I don't used the thermistors I cannot turn the heaters on, but the fan does turn on, using the 7 switch and DIO14.
I've seen people have it working by setting the brownout fuse to 2.7V. I have not seen a report of the workaround in the above link to work for anything more than the motors.

Honestly, I'm suprised what Marlin is doing here. Gen7's circuitry is pretty much the same as the ones of RAMPS and Sanguinololu, so it should work the same way.

Marlin's non-support for 20 MHz was solved quite some time ago and it has been working on a Gen7: [reprap.org] . No idea what's going on now.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

644p original has 4k
1284p has up to 16k ram!
if there are issues getting it to work consider that the stack is overflowing into variable data and corrupting the running of the firmware software. there is 1/4 of ram for older chips.
reduce buffers in adv config file. hope this helps.

if it does not work in pronterface, user arduino serial monitor terminal at baud rate specified. when chip initializes bytes free should show up as a monitor status in the terminal.


i was able to fit marlin in a 328, but it would only init with terminal program. not enough ram, chip crashed. you may be out of ram and having unreliable operation.

Edited 1 time(s). Last edit at 08/12/2012 05:45PM by jamesdanielv.