M7 CHIP_FREQ_CPU_MAX 120MHz

Go To Last Post
3 posts / 0 new
Author
Message
#1
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

I studied some ASF header files (e.g. version 3.40) and found the following constant

 

#define CHIP_FREQ_CPU_MAX               (120000000UL)

 

e.g. in the file

 

\src\ASF\sam\utils\cmsis\same70\include\same70q21b.h

 

I thought that the max. M7 CPU clock is 300 MHz ?

SAME newbie

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

// ===== Target frequency (Processor clock)
// - XTAL frequency: 12MHz
// - System clock source: PLLA
// - System clock prescaler: 1 (divided by 1)
// - System clock divider: 2 (divided by 2)
// - PLLA source: XTAL
// - PLLA output: XTAL * 25 / 1
// - Processor clock: 12 * 25 / 1 / 1 = 300MHz
// - System clock: 300 / 2 = 150MHz

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

 

Yepp, I know but the define e.g. in same70q21.h do not match to this

 

/* Device characteristics */
#define CHIP_FREQ_SLCK_RC_MIN           (20000UL)
#define CHIP_FREQ_SLCK_RC               (32000UL)
#define CHIP_FREQ_SLCK_RC_MAX           (44000UL)
#define CHIP_FREQ_MAINCK_RC_4MHZ        (4000000UL)
#define CHIP_FREQ_MAINCK_RC_8MHZ        (8000000UL)
#define CHIP_FREQ_MAINCK_RC_12MHZ       (12000000UL)
#define CHIP_FREQ_CPU_MAX               (120000000UL)
#define CHIP_FREQ_XTAL_32K              (32768UL)
#define CHIP_FREQ_XTAL_12M              (12000000UL)

 

The define can be used for flash initialization e.g. for

 

system_init_flash(CHIP_FREQ_CPU_MAX);

 

If clock initialization is successful CPU is running at 300MHz and if flash initialization is done according to this everything should be OK but nevertheless this define is wrong or am I wrong ?

SAME newbie