MK30DN512ZVLK10 Freescale Semiconductor, MK30DN512ZVLK10 Datasheet - Page 929

• Manufacturer Part Number: MK30DN512ZVLK10
• Description: ARM Microcontrollers - MCU KINETIS 512K SLCD
• Manufacturer: Freescale Semiconductor

Specifications of MK30DN512ZVLK10

• Core: ARM Cortex M4
• Processor Series: K30
• Data Bus Width: 32 bit
• Maximum Clock Frequency: 50 MHz
• Program Memory Size: 512 KB
• Data Ram Size: 128 KB
• On-chip Adc: Yes
• Operating Supply Voltage: 1.71 V to 3.6 V
• Operating Temperature Range: - 40 C to + 105 C
• Package / Case: LQFP-80
• Mounting Style: SMD/SMT

37.4.2 Interrupts
All of the timers support interrupt generation. Refer to the MCU specification for related
vector addresses and priorities.
Timer interrupts can be enabled by setting the TIE bits. The timer interrupt flags (TIF)
are set to 1 when a timeout occurs on the associated timer, and are cleared to 0 by writing
a 1 to that TIF bit.
37.5 Initialization and Application Information
In the example configuration:
First the PIT module must be activated by writing a 0 to the MDIS bit in the MCR.
The 50 MHz clock frequency equates to a clock period of 20 ns. Timer 1 needs to trigger
every 5.12 ms/20 ns = 256000 cycles and timer 3 every 30 ms/20 ns = 1500000 cycles.
The value for the LDVAL register trigger is calculated as:
LDVAL trigger = (period / clock period) -1
This means LDVAL1 should be written with 0x0003E7FF, and LDVAL3 should be
written with 0x0016E35F.
The interrupt for Timer 1 is enabled by setting TIE in the TCTRL1 register. The timer is
started by writing 1 to bit TEN in the TCTRL1 register.
Timer 3 shall be used only for triggering. Therefore Timer 3 is started by writing a 1 to
bit TEN in the TCTRL3 register, bit TIE stays at 0.
The following example code matches the described setup:
Freescale Semiconductor, Inc.
• The PIT clock has a frequency of 50 MHz.
• Timer 1 creates an interrupt every 5.12 ms.
• Timer 3 creates a trigger event every 30 ms.
// turn on PIT
PIT_MCR = 0x00;
// Timer 1
PIT_LDVAL1 = 0x0003E7FF; // setup timer 1 for 256000 cycles
PIT_TCTRL1 = TIE; // enable Timer 1 interrupts
PIT_TCTRL1 |= TEN; // start Timer 1
// Timer 3
K30 Sub-Family Reference Manual, Rev. 6, Nov 2011
Chapter 37 Periodic Interrupt Timer (PIT)
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