When I halt the CPU in the infinite loop I can see that my PC is at 0x03fe88b0, if I subtract 0x3fc5000 = 0x000238b4 in flash = 0xfff238b4...according to u-boot.map this is the function serial_getc() which seems that u-boot is running and waiting for an input, and I still don't have any display on my console.
I have tried both serial ports with no results. I changed the baud rate also.
Scott: How can you write something in the serial port with the BDI it looks like you have to set many registers before sending one byte through the serial cable?
I will investigate more and let you know, I am glad that u-boot is running!
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@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?"