10 replies to this topic

[AnubisI]

Hi,

 

I received my first Mini 3 days ago. I also purchased a USB-RS232 adapter.

Since then I have been trying to flash Tinybooter and NETMF onto the Mini. After reading all forum posts regarding communication problems I am still unable to receive any sign of life from it.

I tested SAM-BA 2.12, 2.10 and 2.8 under Win8, Win7 and Windows Server 2008. The first 2 with the USB adapter (since these PCs don't have serial ports) and the last one with a 7 year old PC I had around (which has 2 COM ports). I tried to use a 12V regulated power supply as well as a 5V, switched the TX and RX cables, erased the Mini ~100 times, but still no success (Neither Sam-BA nor Putty nor Termite nor MFDeploy)

 

The cable seems to be fine, if I connect the TX and RX directly, I get loopbacks with Termite.

 

You can find a picture of my setup in the attached file (note that I use the regulated 5V of a Gadgeteer as input).

 

I am a bit frustrated now, I hope you can help me resolve the problem.

 

Thanks

Attached Files

•  WP_20130730_002.jpg   76.96KB   3 downloads

[NooM]

your wireing seems strange.

 

you have to use pin 1, 2 and 3

you are using 2,3 and gnd.

(yes ok you have to connect both gnd's together if you use a external power supply)

 

you flash the tinybooter via samba over the rs232 port (pin 1,2 and 3) with 12v.

depending on wich booter you flash you can than flash the netmf with either 12v rs 232 or 3.3v uart (pin 11 and 12)

[NooM]

i just wanted to add: did you erase it with 3.3v ? erasing with 5v may damage the uC.. maybe not the first time, but if you do it a 100 times ...

[AnubisI]

Hi,

thanks for your reply.

I thought 1 and 2 would be RX and TX, respectively, 3 DTR which is not needed necessarily (although I tried connecting it) and 4 is the signals ground. Also, I think my wiring is correct, but it looks a bit strange in the picture due to the perspective - sorry for that.

I did erase with 5V, as I read in some posts... (and it weren't really 100 attempts )

 

So sadly, this does not really help :/

[cys]

I would suggest checking the continuity of all wires/pins "in situ." Also try different locations on the breadboard. Jiggle things. Samba is sensitive and breadboards don't always give the best contact for parts.

[cys]

Not all USB-RS232 adapters are created equal. Samba is touchy. Also, I found drivers for many adapters to be unreliable. It's safest to use an adapter that has been previously shown to work, or else you are in uncharted territory... I know this first hand, but it's been noted in this forum before by others.

[Chris Walker]

Hi AnubisI, Before erasing the board, were you able to communicate with the pre-existing firmware on the board? Also, as cys mentioned, SAM-BA doesn't agree well with some USB-RS232 adapters. We use Keyspan USA-19HS here. Chris

[AnubisI]

Hi,

 

thanks for your answers and sorry for my delays, I currently do not have much time to try things since I am in my exam phase...

As cys suggests, I will try some positions on the breadboard and check my cable. I also ordered a Keyspan, just to be sure before returning the Mini (it's pricey - but hopefully I can just return it unused or barely used :/).

 

@Chris: Sadly, I forgot to test that since I wanted to use the latest firmware. Therefore I started trying to install it immediately...

 

I will report my progress as soon as I had the chance to test the suggestions.

 

Thanks for your support,

AnubisI

[cys]

I use a Keyspan per one of Chris' earlier recommendations. I find it works very well, in contrast to a string of others I had tried before changing to it. I use the Keyspan all the time in my work flow with the mini. Once you get the protocol worked out, all should be good. Been there, done that. I've never destroyed a mini yet.

[NooM]

hm, to reflash iam using a cp2102 + max232 - cheapo solution and works great.

when i use the ttl (uart) port from programming i just remove the max232

 

a note: the cp2102 is like 3$ and a max232 with 4 caps also around 3$ ..

[AnubisI]

Apparently, the Keyspan did the trick.

I was able to deploy TinyBooter, TinyCLR and I am running the first program (a blinking LED - WOHOO )

 

Thank you for your help, I am glad I did not damage the Mini and can now move on with the actual work

 

Greetings,

AnubisI