• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 98 subscribers
  • Views 574 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

AM335X Initialization Questions

ming peng
Prodigy 165 points

Hi, i saw am335x technical reference manual. in chapter 26, described Initialization. i understand LCD_DATA 0-15 are sysboot pin, pulldown or pullup will correspond to relative boot sequence.e.g  0100000000111100 is for MMC1,MMC0, UART0, USB0 booting.  also, each pad has pad control registers to enable internal pull down/pull up.   so,

1 what's the default config for pad control registers of LCD_DATA 0-15?  

2 can i eliminate the external pull down/pull up resistors for sysboot?  

moreover, there are control_status Register, bit 0-7 and 16-23 response to sysboot 0-15,

3  what's the default config on control_status Register?  

4 how can i got 0100000000111100  for MMC1,MMC0, UART0, USB0 booting sequence by Software without set pull down/ pull up resistors by Hardware in the first initialization?  is it possible? 

many thanks. 

  • 0
    TI__Guru**** 393215 points

    Hi,

    ming peng said:
    1 what's the default config for pad control registers of LCD_DATA 0-15?  

    See Table 4-1 in the AM335X Datasheet Rev. G. Columns "BALL RESET STATE", "BALL RESET RELEASE STATE" and "RESET RELEASE MODE" are what you are looking for.

    ming peng said:
    2 can i eliminate the external pull down/pull up resistors for sysboot?  

    No.

    ming peng said:
    3  what's the default config on control_status Register?

    See section 9.3.1.4 in the AM335X TRM Rev. L.

    ming peng said:
    4 how can i got 0100000000111100  for MMC1,MMC0, UART0, USB0 booting sequence by Software without set pull down/ pull up resistors by Hardware in the first initialization?  is it possible? 

    No.