Counter0 Mode0

Macros
#define	T0   P34
	T0 pin definition.

init
Counter initializaion functions
#define	counter0_mode0_init()
	Initialize mode0 for counter0.

run
Counter run/stop/reload functions
#define	counter0_mode0_start(value)
	Run counter0.
#define	counter0_mode0_stop()
	Stop counter0.
#define	is_counter0_mode0_started()   (TR0 == 1 && (is_counter0_mode0_gate_opened() || INT0 == 1) )
	Get counter0 mode0 started status.

read/write
Counter get and set value functions
#define	counter0_mode0_get_value()   ((((uint16_t) TH0) << 8) | TL0)
	get counter0 value in mode0
#define	counter0_mode0_set_value(value)
	set counter0 value in mode0

config
Counter0 pin output and gate config functions
#define	counter0_mode0_enable_P35_output()   (bit_set(INT_CLKO, SBIT0))
	enable output to P3.5
#define	counter0_mode0_disable_P35_output()   (bit_clr(INT_CLKO, CBIT0))
	disable output to P3.5
#define	is_counter0_mode0_P35_output_enabled()   (test_if_bit_set(INT_CLKO, SBIT0))
	get pin P3.5 output state to P3.5
#define	counter0_mode0_open_gate()   (bit_clr(TMOD, CBIT3))
	Open counter0 gate.
#define	counter0_mode0_close_gate()   (bit_set(TMOD, SBIT3))
	Close counter0 gate.
#define	is_counter0_mode0_gate_opened()   (test_if_bit_cleared(TMOD, SBIT3))
	Get gate state.

Detailed Description

Functions and data structures for counter0 mode0.

This module supports general purpose counter0. Mode0 is auto reload 16-bit counter.

Counter0 increments its value on T0 pin change state from 0 to 1. Once the counter reaches its maximum value of 65535, the counter is reset to zero at the next increment. On counter overflow reset interrupt 1 is raised.

Author

Michael Golovanov

Macro Definition Documentation

counter0_mode0_close_gate

#define counter0_mode0_close_gate

(

)

(bit_set(TMOD, SBIT3))

Close counter0 gate.

Closing gate stop counter0.

counter0_mode0_disable_P35_output

#define counter0_mode0_disable_P35_output

(

)

(bit_clr(INT_CLKO, CBIT0))

disable output to P3.5

Disable pin P.3.5 state changes on counter0 overflow. By default P3.5 output is disabled

counter0_mode0_enable_P35_output

#define counter0_mode0_enable_P35_output

(

)

(bit_set(INT_CLKO, SBIT0))

enable output to P3.5

Enable pin P.3.5 state changes on counter0 overflow. By default P3.5 output is disabled

counter0_mode0_get_value

#define counter0_mode0_get_value

(

)

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

get counter0 value in mode0

Returns

uint16_t counter value

counter0_mode0_init

#define counter0_mode0_init

(

)

Value:

do {                                            \
    enable_mcu_interrupts();                    \
    enable_timer0_interrupt();                  \
                                                \
    /* TMOD.3/GATE = 0; */                      \
    /* TMOD.2/(Timer or Counter mode) = 1; */   \
    /* TMOD.1/M1 timer0 = 0; */                 \
    /* TMOD.0/M0 timer0= 0; */                  \
    TMOD |= 0x04; /* init Counter0 */           \
} while(0)

Initialize mode0 for counter0.

Enable counter0 interrupt and set mode0

counter0_mode0_open_gate

#define counter0_mode0_open_gate

(

)

(bit_clr(TMOD, CBIT3))

Open counter0 gate.

When gate is opened counter0 will count. By default after init gate is opened. This routine explicitly open the gate.

counter0_mode0_set_value

#define counter0_mode0_set_value

(

value

)

Value:

do {                                            \
    TH0 = (uint8_t)(value >> 8);                \
    TL0 = (uint8_t)(value & 0xff);              \
} while(0)

set counter0 value in mode0

Call this method before counter0 started.

Parameters

value

uint16_t counter value to set

counter0_mode0_start

#define counter0_mode0_start

(

value

)

Value:

do {                                            \
    counter0_mode0_set_value(value);            \
                                                \
    TF0 = 0;                                    \
    TR0 = 1;                                    \
} while (0);

Run counter0.

Before run counter0_mode0_init should be called. After run counter0 is counted T0 pin state change. Interrupt handler void timer0ISR(void) __interrupt(1) should be defined in user code.

Parameters

value

uint16_t initial counter value

counter0_mode0_stop

#define counter0_mode0_stop

(

)

Value:

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

Stop counter0.

Stop count T0 pin state changes. Before stop counter0_start should be called.

is_counter0_mode0_gate_opened

#define is_counter0_mode0_gate_opened

(

)

(test_if_bit_cleared(TMOD, SBIT3))

Get gate state.

returns bool. True if gate is opened and false if gate is closed

is_counter0_mode0_P35_output_enabled

#define is_counter0_mode0_P35_output_enabled

(

)

(test_if_bit_set(INT_CLKO, SBIT0))

get pin P3.5 output state to P3.5

Returns

true if P3.5 output enabled otherwise false

is_counter0_mode0_started

#define is_counter0_mode0_started

(

)

(TR0 == 1 && (is_counter0_mode0_gate_opened() || INT0 == 1) )

Get counter0 mode0 started status.

Returns

bool true if started otherwise false