NetBurner Community Forum

Hello out there…

Just received a SBL2e-100IR unit and am trying to get an indication that it’s alive. As I understand it from Marc’s post of 2/28/11 “Newbie on SBL2e: how to power up card”, I need +3.3 v on pin 5, relative to ground on pin 6. (The two adjacent pins, third pair down from the 16-pin header's top...) With just that, I should see brief LED action on the RJ-45 jack. Then when plugged into the network hub, one LED ought to flicker in the usual fashion.

With voltage on, I’m getting a 75 ma draw, but no LEDs with or without a network cable. And no recognition by the network.

Does this mean the unit was brain-DOA?

Thanks!

Hi,
The only two signals you need are the ones you indicated. On JP1 (16-pin header ), Pin5 gets 3.3V and Pin6 goes to GND... Pin11 can go to GND too. Make sure you follow the data sheet for proper pin locations ( http://www.netburner.com/downloads/sbl2 ... iption.pdf )

What are you using for a power supply, what is the max current? Linear power supplies often have trouble providing enough current to fully power these boards. I highly recommend having an eval board for debugging as custom hardware issues can be instantly ruled out. Have you looked at the UARTs to see if there is any communication? The likely hood that the module is DOA is extreamly low, especially the L2e since they are single chip. Before shipping the module is fully tested all pins along with network tests directly using the factory application.

-Larry

Thanks Larry...

I'm using an HP bench supply with a selectable range for current limiting. I set the open circuit voltage to 3.3 using a digital DVM, connected up the unit, and then clicked through the current limits starting at the min, until the voltage restabilized at 3.3, measured on the header pins. (For this simple go/no-go test, I just wire-wrapped to terminals 5 & 6 on the header.) The internal meter then showed 70 ma when set at the 100 ma max range. [When I get home, I'll try Marc's 2 D-cell supply, just to cover the bases...]

Anyway, during all of my power-on attempts, I've yet to see a photon from the RJ-45 LEDs. Without any response there, I can't see any way forward...

Do I understand from your message that the UART might be reporting something useful during power up?

I'm trying to do a really simple unidirectional remote serial interface onto my network, so I wanted to avoid the bells, whistles, and expense of the eval board.

--Mike

Microcontrollers can b sensitive to long rise times. If you slowly bring up power, they can get into a bad state. I think that is one of the reasons most companies recommend using an eval board, in addition to having a known good circuit for the RS-232 connection for the console port. One thing you could try is to set up your bench top supply to 3.3V, and current limit of 400mA, and without stepping it up just turn it on. It should power-up quick enough for the processor to work correctly.