Free-Running Timer (FRT)

Macros
#define	CPU_FRT_CLOCK_DIV_8   0x00
#define	CPU_FRT_CLOCK_DIV_32   0x01
#define	CPU_FRT_CLOCK_DIV_128   0x02
#define	CPU_FRT_CLOCK_DIV_RISING_EDGE   0x03
	Not yet documented.
#define	CPU_FRT_NTSC_320_8_COUNT_1MS   0x0D1F
#define	CPU_FRT_NTSC_320_32_COUNT_1MS   0x0348
#define	CPU_FRT_NTSC_320_128_COUNT_1MS   0x00D2
#define	CPU_FRT_NTSC_352_8_COUNT_1MS   0x0DFC
#define	CPU_FRT_NTSC_352_32_COUNT_1MS   0x037F
#define	CPU_FRT_NTSC_352_128_COUNT_1MS   0x00E0
#define	CPU_FRT_PAL_320_8_COUNT_1MS   0x0D08
#define	CPU_FRT_PAL_320_32_COUNT_1MS   0x0342
#define	CPU_FRT_PAL_320_128_COUNT_1MS   0x00D0
#define	CPU_FRT_PAL_352_8_COUNT_1MS   0x0DFC
#define	CPU_FRT_PAL_352_32_COUNT_1MS   0x037F
#define	CPU_FRT_PAL_352_128_COUNT_1MS   0x00E0

Typedefs
typedef void(*	cpu_frt_ihr_t) (void)
	Callback type.

Functions
static void	cpu_frt_count_set (uint16_t count)
	Set the 2-byte FRT tick count.
static uint16_t	cpu_frt_count_get (void)
	Obtain the current 2-byte FRT tick count.
static uint16_t	cpu_frt_input_capture_get (void)
	Obtain the ICR value.
static uint8_t	cpu_frt_interrupt_priority_get (void)
	Obtain the interrupt priority level for CPU-FRT.
static void	cpu_frt_interrupt_priority_set (uint8_t priority)
	Set the interrupt priority level for CPU-FRT.
void	cpu_frt_init (uint8_t clock_div)
	Fully initialize the CPU-FRT depending with a specific clock divisor.

Detailed Description

Description goes here.

Macro Definition Documentation

CPU_FRT_CLOCK_DIV_8

#define CPU_FRT_CLOCK_DIV_8   0x00

Deprecated:

To be removed and replaced as an enum.

CPU_FRT_CLOCK_DIV_32

#define CPU_FRT_CLOCK_DIV_32   0x01

Deprecated:

To be removed and replaced as an enum.

CPU_FRT_CLOCK_DIV_128

#define CPU_FRT_CLOCK_DIV_128   0x02

Deprecated:

To be removed and replaced as an enum.

CPU_FRT_NTSC_320_8_COUNT_1MS

#define CPU_FRT_NTSC_320_8_COUNT_1MS   0x0D1F

Tick count value representing 1ms for a NTSC machine in 320-mode with a \(\frac{\phi}{8}\) clock divisor.

CPU_FRT_NTSC_320_32_COUNT_1MS

#define CPU_FRT_NTSC_320_32_COUNT_1MS   0x0348

Tick count value representing 1ms for a NTSC machine in 320-mode with a \(\frac{\phi}{32}\) clock divisor.

CPU_FRT_NTSC_320_128_COUNT_1MS

#define CPU_FRT_NTSC_320_128_COUNT_1MS   0x00D2

Tick count value representing 1ms for a NTSC machine in 320-mode with a \(\frac{\phi}{128}\) clock divisor.

CPU_FRT_NTSC_352_8_COUNT_1MS

#define CPU_FRT_NTSC_352_8_COUNT_1MS   0x0DFC

Tick count value representing 1ms for a NTSC machine in 352-mode with a \(\frac{\phi}{8}\) clock divisor.

CPU_FRT_NTSC_352_32_COUNT_1MS

#define CPU_FRT_NTSC_352_32_COUNT_1MS   0x037F

Tick count value representing 1ms for a NTSC machine in 352-mode with a \(\frac{\phi}{32}\) clock divisor.

CPU_FRT_NTSC_352_128_COUNT_1MS

#define CPU_FRT_NTSC_352_128_COUNT_1MS   0x00E0

Tick count value representing 1ms for a NTSC machine in 352-mode with a \(\frac{\phi}{128}\) clock divisor.

CPU_FRT_PAL_320_8_COUNT_1MS

#define CPU_FRT_PAL_320_8_COUNT_1MS   0x0D08

Tick count value representing 1ms for a PAL machine in 320-mode with a \(\frac{\phi}{8}\) clock divisor.

CPU_FRT_PAL_320_32_COUNT_1MS

#define CPU_FRT_PAL_320_32_COUNT_1MS   0x0342

Tick count value representing 1ms for a PAL machine in 320-mode with a \(\frac{\phi}{32}\) clock divisor.

CPU_FRT_PAL_320_128_COUNT_1MS

#define CPU_FRT_PAL_320_128_COUNT_1MS   0x00D0

Tick count value representing 1ms for a PAL machine in 320-mode with a \(\frac{\phi}{128}\) clock divisor.

CPU_FRT_PAL_352_8_COUNT_1MS

#define CPU_FRT_PAL_352_8_COUNT_1MS   0x0DFC

Tick count value representing 1ms for a PAL machine in 352-mode with a \(\frac{\phi}{8}\) clock divisor.

CPU_FRT_PAL_352_32_COUNT_1MS

#define CPU_FRT_PAL_352_32_COUNT_1MS   0x037F

Tick count value representing 1ms for a PAL machine in 352-mode with a \(\frac{\phi}{32}\) clock divisor.

CPU_FRT_PAL_352_128_COUNT_1MS

#define CPU_FRT_PAL_352_128_COUNT_1MS   0x00E0

Tick count value representing 1ms for a PAL machine in 352-mode with a \(\frac{\phi}{128}\) clock divisor.

Typedef Documentation

cpu_frt_ihr_t

typedef void(* cpu_frt_ihr_t) (void)

Callback type.

See also

cpu_frt_oca_set

cpu_frt_ocb_set

cpu_frt_ovi_set

Function Documentation

cpu_frt_count_set()

static void cpu_frt_count_set ( uint16_t  count )

inlinestatic

Set the 2-byte FRT tick count.

Parameters

count

The 2-byte tick value to set.

cpu_frt_count_get()

static uint16_t cpu_frt_count_get ( void  )

inlinestatic

Obtain the current 2-byte FRT tick count.

Returns

Return the 2-byte FRT tick count.

cpu_frt_input_capture_get()

static uint16_t cpu_frt_input_capture_get ( void  )

inlinestatic

Obtain the ICR value.

When a rising edge or falling edge of the input capture signal is detected, the current FRT tick count value is transferred to the ICR.

Returns

The ICR value.

cpu_frt_interrupt_priority_get()

static uint8_t cpu_frt_interrupt_priority_get ( void  )

inlinestatic

Obtain the interrupt priority level for CPU-FRT.

Returns

The interrupt priority level ranging from 0 to 15.

cpu_frt_interrupt_priority_set()

static void cpu_frt_interrupt_priority_set ( uint8_t  priority )

inlinestatic

Set the interrupt priority level for CPU-FRT.

Parameters

priority

The priority ranging from 0 to 15.

cpu_frt_init()

void cpu_frt_init

(

uint8_t

clock_div

)

Fully initialize the CPU-FRT depending with a specific clock divisor.

This function is heavy handed in that it resets the interrupt priority levels for all FRT related interrupts, clears the interrupt handlers, and resets the FRT count.

This function will properly initialize the CPU-FRT on either the master or slave CPU.

Parameters

clock_div

The clock divisor.