[U-Boot-Users] U-Boot problems with MPC8272ADS

[Jerry Van Baren]

Scott Wood wrote:
> Manil Gaouar wrote:
>> I installed u-boot on my mpc8272ads board, and when I connect the
>> board with a serial link to my pc, I don’t see any output in the
>> console, I use cu S0 at 115200, I have connected a JTAG to see what’s
>> happening in the board I can see that the PC register is changing and
>> going through the memory, and the pc will be stuck in an infinite
>> loop which means that he is waiting for an input,
> 
> That's hardly the only case in which code can get stuck in an infinite loop.

When you halt the CPU with the JTAG, what the PC value?  Look it up in 
your u-boot link map, where is it looping?

>> probable the command prompt. I have compared different positions in
>> my PC register and the u-boot.map and I can see which function my
>> code is at, so u-boot is running, but why I don’t have a display??
> 
> Did you check that the serial port is properly initialized, including 
> I/O pin and BRG setup?  Can you get serial output by manually poking the 
> registers with the BDI?
> 
> -Scott

The second dumbest question: did you plug your serial cable into _both_ 
of the mpc8272ads board's serial ports?

The third dumbest question: did you try different baud rates on your PC 
(or, better, look at the board's serial output with an o'scope)?

gvb
P.S. The first dumbest question is "Is it plugged in?"