Hi, I'm going to fire-up my RM9200 board. I see that CPU is sending letter (but not XModem "CCCCC") on DBG-UART. The problem is that CPU is doing it to fast - one bit of that char tooks about 4,56us - I'm thinking that something wrong is with PLL. Can somebody be so kind and measure for me the amplitude on 18,432MHz crystal pins and the voltage on PLL-RCA and PLL-RCB pins ? thanks a lot! -- Pelos http://www.pelos.pl
AT91RM9200 - PLL's - Main CLK
Started by ●August 18, 2006
Reply by ●August 19, 20062006-08-19
In comp.arch.embedded, Pelos @ Home <pelos@pelos.pl> wrote:> Hi, > I'm going to fire-up my RM9200 board. > I see that CPU is sending letter (but not XModem "CCCCC") on DBG-UART. > The problem is that CPU is doing it to fast - one bit of that char tooks > about 4,56us - I'm thinking that something wrong is with PLL. > Can somebody be so kind and measure for me the amplitude on 18,432MHz > crystal pins and the voltage on PLL-RCA and PLL-RCB pins ? >Sorry no time to measure it now. But I also had problems getting the right xmodem char. Which was usually solved by pressing reset again. This chip really needs a long power-up reset (> 1s). This is in the datasheet but I had missed it first time. When I changed my POR circuit, the problem was solved. -- Stef (remove caps, dashes and .invalid from e-mail address to reply by mail)
Reply by ●August 19, 20062006-08-19
Stef wrote:> In comp.arch.embedded, > Pelos @ Home <pelos@pelos.pl> wrote: > >>Hi, >>I'm going to fire-up my RM9200 board. >>I see that CPU is sending letter (but not XModem "CCCCC") on DBG-UART. >>The problem is that CPU is doing it to fast - one bit of that char tooks >>about 4,56us - I'm thinking that something wrong is with PLL. >>Can somebody be so kind and measure for me the amplitude on 18,432MHz >>crystal pins and the voltage on PLL-RCA and PLL-RCB pins ? >> > > Sorry no time to measure it now. But I also had problems getting the right > xmodem char. Which was usually solved by pressing reset again. This chip > really needs a long power-up reset (> 1s). This is in the datasheet but > I had missed it first time. When I changed my POR circuit, the problem > was solved. >Hi Stef, Thanks for your suggestion. I will check it :-) -- Pelos http://www.pelos.pl
Reply by ●August 21, 20062006-08-21
Stef wrote:> In comp.arch.embedded, > Pelos @ Home <pelos@pelos.pl> wrote: > >>Hi, >>I'm going to fire-up my RM9200 board. >>I see that CPU is sending letter (but not XModem "CCCCC") on DBG-UART. >>The problem is that CPU is doing it to fast - one bit of that char tooks >>about 4,56us - I'm thinking that something wrong is with PLL. >>Can somebody be so kind and measure for me the amplitude on 18,432MHz >>crystal pins and the voltage on PLL-RCA and PLL-RCB pins ? >> > > Sorry no time to measure it now. But I also had problems getting the right > xmodem char. Which was usually solved by pressing reset again. This chip > really needs a long power-up reset (> 1s). This is in the datasheet but > I had missed it first time. When I changed my POR circuit, the problem > was solved. >Hi Stef, Thanks a lot ! It works fine :) Now I'm trying to flash my SPI DataFlash. Best regards, -- Pelos http://www.pelos.pl