Counter0 Mode1

Macros
#define	T0   P34
	T0 pin definition.
#define	INT0   P32
	INT0 pin definition.

init
Counter initializaion functions
#define	counter0_mode1_init()
	Initialize mode1 for counter0.

start/stop
Counter0 start/stop functions
#define	counter0_mode1_start(value)
	Starts Counter 0 in Mode 1 with a specified initial value.
#define	is_counter0_mode1_started()   (TR0 == 1)
	Check if counter0 is started.
#define	counter0_mode1_stop()
	Stop counter0.

read
Counter read value functions
#define	counter0_mode1_get_value()   ((((uint16_t) TH0) << 8) | TL0)
	Get counter0 value in mode1.

Detailed Description

Counter0 mode 1 routines.

This module supports general purpose counter0. Timer can work as COUNTER or TIMER.

Counter increments on T0 pin change state.

Counter0 Mode1 is 16-bit counter. Mode1 is like mode0 but without reloading and P35 pin output features.

Author

Michael Golovanov

Macro Definition Documentation

counter0_mode1_get_value

#define counter0_mode1_get_value

(

)

((((uint16_t) TH0) << 8) | TL0)

Get counter0 value in mode1.

Returns

uint16_t counter value

counter0_mode1_init

#define counter0_mode1_init

(

)

Value:

do {                                            \
    enable_mcu_interrupts();                    \
    enable_timer0_interrupt();                  \
                                                \
    TMOD &= 0xF0;                               \
    TMOD |= 0x05;                               \
                                                \
    TF0 = 0;                                    \
    TR0 = 0;                                    \
} while(0)

Initialize mode1 for counter0.

Enable counter0 interrupt and set mode1.

Mode 1 is configured as setting TMOD lowest 4 bytes:

• TMOD.0 = 1
• TMOD.1 = 0
• TMOD.2 = 1
• TMOD.3 = 0

Attention

Interrupt handler void counter0ISR(void) __interrupt(1) should be defined in user code.

counter0_mode1_start

#define counter0_mode1_start

(

value

)

Value:

do {                                            \
    static_assert(value <= 0xffff, "value is too large"); \
                                                \
    const uint16_t _val = value;                \
    TH0 = (uint8_t) (_val >> 8);                \
    TL0 = (uint8_t) (_val & 0xFF);              \
                                                \
    TF0 = 0;                                    \
    TR0 = 1;                                    \
} while(0)

Starts Counter 0 in Mode 1 with a specified initial value.

Loads the initial 16-bit value into Counter 0 registers and starts the counter.

Attention

Before calling this function, counter0_mode1_init() should be called.

Parameters

value

16-bit unsigned integer specifying the initial counter count

counter0_mode1_stop

#define counter0_mode1_stop

(

)

Value:

do {                                            \
    TR0 = 0;                                    \
    TF0 = 0;                                    \
} while(0)

Stop counter0.

Stop counter0 and clear TF0 flag.

is_counter0_mode1_started

#define is_counter0_mode1_started

(

)

(TR0 == 1)

Check if counter0 is started.

Returns

true if counter0 started otherwise false