TWR-K60N512-KEIL Freescale Semiconductor, TWR-K60N512-KEIL Datasheet - Page 14

• Manufacturer Part Number: TWR-K60N512-KEIL
• Description: K60N512 Keil Tower Kit
• Manufacturer: Freescale Semiconductor
• Series: Kinetisr
• Type: MCUr

Specifications of TWR-K60N512-KEIL

• Rohs Compliant: YES
• Contents: 4 Boards, Documentation, DVD
• Peak Reflow Compatible (260 C): Yes
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: Freescale Tower System, K60N512

Typical system initialization
1.3.1 Device state during reset
With the exception of the JTAG pins, during reset the digital I/O pins go to a disabled
(high impedance) state with internal pullups/pulldowns disabled. Pins with analog
functionality will default to their analog functions.
1.3.2 Device state after reset
After reset the digital I/O pins remain disabled until enabled by software. Also, interrupts
are disabled and the clocks to most of the modules are off. The default clock mode after
reset is FLL Engaged Internal (FEI) mode. In this mode the system is clocked by the
frequency-locked loop (FLL) using the slow internal reference clock as its reference. The
watchdog timer is active; therefore it will need to be serviced (or disabled if debugging).
The core clock, system clock, and flash clock are enabled after reset to support booting.
Also, the flash memory controller cache and prefetch buffers are enabled.
1.4 Typical system initialization
The following is a summary of typical software initialization. The code snippets are taken
from a "hello_world" project written in IAR Embedded Workbench. This project is
available in the Kinetis sample code found in the file KINETIS512_SC.zip which
accompanies this users guide.
1.4.1 Lowest level assembly routines
These routines are assembly source code found in the file crt0.s. The address of the start
of this code is placed in the vector table offset 4 (initial program counter) so that it is
executed first when the processor starts up. This is accomplished by labeling this section,
exporting the label, and placing the label in the vector table. The vector table can be
found in vectors.h. In this example the label used is __startup.
1.4.1.1 Initialize general purpose registers
As a general rule, it is recommended to initialize the processor general purpose registers
(R0-R12) to zero. This is done with the move instruction.
Kinetis Quick Reference User Guide, Rev. 0, 11/2010
14
Freescale Semiconductor