Can't connect through USB-TTL

Hi,

I've etched and soldered a Gen7 1.4 board and all seems to works well:

• I've been able to burn the bootloader by using an Arduino Mega as ISP
• I've been able to upload the SetupTest sketch by using an USB 2.0 to UART TTL CP2102
• I've been able to upload the Teacup_Firmware

But I'm frustrating when I'm trying to connect to the board using Pronterface (either gtkterm, Arduino serial monitor, and so on). Nothing happens. Just `connecting...'

I've given a try to Sprinter, and Pronterface still refusing to connect, but gtkterm shows me, every 3 seconds, the initial message:

Sprinter
1.3.22T / 20.08.2012
start
Soft PWM Init
Planner Init
Stepper Timer init
Free Ram: 1060
Plan Buffer Size:1152 / 16

Like said, every 3 seconds the `data' LED in the USB-TTL blinks, and the message appears.

My electronics knowledge is near to zero, so is it possible that some components, like the coil (it's only 165mA rated) or the crystal, are doing something wrong, or is it related to the ATmega itself? I've tryed both ATmega644P and ATmega1284P. The oscillator is 20MHz. None in the board is shorted, and all routes has been checked.

Thanks.

Updated. I forgot to mention that I haven't the ATX connector soldered (It's hard to find , and I'm feed the electronics by using both HDD connectors. 5V jumper is plugged correctly.

Edited 1 time(s). Last edit at 01/26/2013 04:01PM by xoan.

Quote

But I'm frustrating when I'm trying to connect to the board using Pronterface (either gtkterm, Arduino serial monitor, and so on). Nothing happens. Just `connecting...'

I've given a try to Sprinter, and Pronterface still refusing to connect, but gtkterm shows me, every 3 seconds, the initial message:

3 seconds is about the time the bootloader waits for incoming connections after a reset. So your board apparently resets immediately after firmware startup.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

Traumflug Wrote:
-------------------------------------------------------
> 3 seconds is about the time the bootloader waits
> for incoming connections after a reset. So your
> board apparently resets immediately after firmware
> startup.

Yeah, it is my conclusion too. But at this point, I don't know what or where can I check to find the reason of this constantly reset.

The SetupTest works: I can read the text at 9600 baud, and the LED is ON and OFF, and finally the repeated `ATmega is idle' message is shown; and it's not reseted by the board.

Well, some kind of advance. I install Marlin, and this is what I get:

start
echo: Brown out Reset
Marlin 1.0.0
echo: Last Updated: Jan 27 2013 13:12:13 | Author: (none, default config)
Compiled: Jan 27 2013
echo: Free Memory: 1454  PlannerBufferBytes: 1232

Now I need to figure out what component or path could be the cause of this brownout reset

Hi again,

After some research through net, I found this issue related to 100µH coil, so I just remove it and wire the pads (it's Sunday and I'm not own a 10µH coil), and voila! can connect.

I've reinstalled Teacup, my first choice, and I can move motors and other stuff. I also can start heaters, but I don't have any resistor connected to them, and LEDs are a bit light when temp is set to 0 and becomes bright when change temp, but this is a question for another time (or maybe not, if it's the normal behaviour --I need to learn more about this things

BTW, thanks for this amazing DIY piece of hardware.

Updated. Is the coil really relevant for other things than the thermistors circuit? Like as I said, I'm not an electronics guy, but I see in the sch file that there is only related to this paths. Sorry if this question is off-topic, or absurd, or whatever.

Edited 1 time(s). Last edit at 01/27/2013 09:14AM by xoan.

Quote

Is the coil really relevant for other things than the thermistors circuit?

No. The coil smoothes analog voltage supply, giving more reliable thermistor readouts. Most other electronics don't have such a coil at all.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY