ATSAM3U-EK Atmel, ATSAM3U-EK Datasheet - Page 470

• Manufacturer Part Number: ATSAM3U-EK
• Description: KIT EVAL FOR AT91SAM3U CORTEX
• Manufacturer: Atmel
• Type: MCUr

Specifications of ATSAM3U-EK

• Contents: Board
• Processor To Be Evaluated: SAM3U
• Data Bus Width: 32 bit
• Interface Type: RS-232, USB
• Operating Supply Voltage: 3 V
• Silicon Manufacturer: Atmel
• Core Architecture: ARM
• Core Sub-architecture: Cortex - M3
• Silicon Core Number: SAM3U4E
• Silicon Family Name: SAM3U
• Kit Contents: Board CD Docs
• Rohs Compliant: Yes
• For Use With/related Products: AT91SAM3U
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

28.12 Clock Switching Details
28.12.1
470
SAM3U Series
Master Clock Switching Timings
Table 28-1
from one selected clock to another one. This is in the event that the prescaler is de-activated.
When the prescaler is activated, an additional time of 64 clock cycles of the new selected clock
has to be added.
Table 28-1.
Notes:
Table 28-2.
To
Main Clock
SLCK
PLL Clock
To
PLLA Clock
UPLL Clock
1. PLL designates either the PLLA or the UPLL Clock.
2. PLLCOUNT designates either PLLACOUNT or UPLLCOUNT.
and
From
Clock Switching Timings (Worst Case)
Clock Switching Timings between Two PLLs (Worst Case)
From
Table 28-2
PLLCOUNT x SLCK +
0.5 x Main Clock +
0.5 x Main Clock +
2.5 x PLLx Clock
Main Clock
give the worst case timings required for the Master Clock to switch
4.5 x SLCK
4 x SLCK +
PLLACOUNT x SLCK
2.5 x PLLA Clock +
3 x UPLL Clock +
1.5 x UPLL Clock
–
PLLA Clock
4 x SLCK +
4 x SLCK +
PLLCOUNT x SLCK
2.5 x PLL Clock +
2.5 x Main Clock
4 x SLCK +
5 x SLCK +
SLCK
–
UPLLCOUNT x SLCK
2.5 x UPLL Clock +
3 x PLLA Clock +
1.5 x PLLA Clock
UPLL Clock
4 x SLCK +
4 x SLCK +
PLLCOUNT x SLCK
2.5 x PLL Clock +
3 x PLL Clock +
3 x PLL Clock +
6430D–ATARM–25-Mar-11
1 x Main Clock
4 x SLCK +
4 x SLCK +
PLL Clock
5 x SLCK