Configuring New IC : Tiva TM4C1294 NCPDT

Hello Rajesh,

There is no special first-use configurations to run TM4C129x's.

Typically, you should configure your clock early in the software according to the crystal you have and the desired frequency.

Pay attention to your GPIO's, make sure that your pins don't send conflicting signals on your custom board, so that a 1 and a 0 don't end up on the same trace... When in doubt, make them all inputs and careful not to copy paste pin configurations from other projects. And then make a very basic led blinker to be sure that your CPU is properly taking firmware and running normally... That's all very basic, but it doesn't hurt to mention.

Which memory location/address are you reading the MAC? Does that reading command works on your launchpad Tiva exactly the same? Still, note that the MAC address that you find on Launchpads is a feature of the LAUNCHPAD itself, not a feature that comes on new TM4C MCU's.

Regards,

Hello Rajesh,

The MAC address do not come as part of the TM4C129x device. You have to get a block of MAC address allocated from IEEE and then use the same on the device by committing the (unofficial) location of the USERREG0 and 1. This has been highlighted in the forum multiple times in the past, so it should be simpler to search the forum too. Please do note that we do not permit reuse of MAC address allocated to TI to customers (unlike USB where VID/PID reuse is allowed by the USB.org)

Hi Amit,

Correct, and this is a post where such is clearly stated:

e2e.ti.com/.../400448

I guess that the MAC address thing can be taken for granted, because lots of projects are born from lauchpads and the number "have just always been there". Maybe the launchpad documentation can stress it a bit further: such MAC Address is a LAUNCHPAD feature, not a bare TM4C129 one.

Regards

Hello Bruno,

Another way of looking at is not everyone wants Ethernet on a TM4C129x. So there is no point providing a preconfigured MAC address.

Amit Ashara said:

not everyone wants Ethernet on a TM4C129x

Yes! Myself, for example!

Most of our TMC4129 boards designs DO have the RJ45 connector and circuit - but we have never had time or need to implement the software for it! (The day will come, of course, and I'll be happy that the connector is there!)

Thanks Bruno and Amit for your reply.

I have used CCS Uniflash to read the MAC address from TM4C1294XL Launchpad where I found a unique MAC address which is same as printed on its back. Now I took my own board and tried to read the MAC address which was found to be 0xffffffffffffffff.
I understood that unique MAC address has to be programmed to the Tiva TM4C1294ncpdt IC which I did using CCS Uniflash(Program and Commit MAC address option). The MAC address is properly programmed which I verified on read.

Now, while connecting Ethernet cable to the Launchpad , two LEDs blink( Port Pin PF0 and PF4)on the board indicating the successful connection.

As per the document (Ref. SW-TM4C-DRL-UG-2.1.1.71, page 270, Description for GPIOPinTypeEthernetLED() ):
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"The Ethernet peripheral provides four signals that can be used to drive an LED (for example, for link status/activity)."

We have used the same uC pins( PF0 and PF1) for our New Board meant for Ethernet LEDs. While connecting the Ethernet cable to our New Board, the LED status is not changing(The Port pins are low). Why Ethernet peripheral is not driving the LED?? The firmware is same for the Launchpad and our New Card.What could be the issue??



Regards,

Rajesh

Hello Rajesg,

Did you write the MAC address to the User registers 0/1 or did you commit the values?

Also is you application checking the User Registers 0/1 or some other address for MAC address?

Hi Amit,
I have checked "Commit MAC Address" option in Uniflash software and Programmed the MAC address value to User 0 and User 1 registers.
Yes my application is checking the User 0 and User 1 register for MAC address.

I have no issue in getting the MAC address while debugging but while reading the port pin for "Ethernet Link OK",
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/* Get the current link status and see if it has changed(Ethernet Link Ok :LED4)*/
bLinkStatusUp = GPIOPinRead(GPIO_PORTF_BASE, GPIO_PIN_0) ? true : false;
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the "bLinkStatusUp " value is not changing. It remains '0' always. It should be driven by the Ethernet peripheral four signals .

What could be the issue???

Hello Rajesh

The Link status is from the Ethernet PHY and not read from the GPIO Pin Read.