Counter0 Mode2

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

init
Counter initializaion functions
#define	counter0_mode2_init()
	Initialize mode2 for counter0.

start/stop
Counter0 start/stop functions
#define	counter0_mode2_start(value)
	Starts Counter 0 in Mode 2 with a specified initial value.
#define	counter0_mode2_stop()
	Stop counter0.
#define	is_counter0_mode2_started()   (TR0 == 1 && (is_counter0_mode2_gate_opened() || INT0 == 1) )
	Get counter0 mode2 started status.

read/write
Counter get and set value functions
#define	counter0_mode2_get_value()   (TL0)
	get counter0 value in mode2
#define	counter0_mode2_set_value(value)
	set counter0 value in mode2

config
Counter0 pin output and gate config functions
#define	counter0_mode2_enable_P35_output()   (bit_set(INT_CLKO, SBIT0))
	enable output to P3.5
#define	counter0_mode2_disable_P35_output()   (bit_clr(INT_CLKO, CBIT0))
	disable output to P3.5
#define	is_counter0_mode2_P35_output_enabled()   (test_if_bit_set(INT_CLKO, SBIT0))
	get pin P3.5 output state to P3.5
#define	counter0_mode2_open_gate()   (bit_clr(TMOD, CBIT3))
	Open counter0 gate.
#define	counter0_mode2_close_gate()   (bit_set(TMOD, SBIT3))
	Close counter0 gate.
#define	is_counter0_mode2_gate_opened()   (test_if_bit_cleared(TMOD, SBIT3))
	Get gate state.

Detailed Description

Counter0 mode 2 routines. This module supports general purpose counter0. Timer can work as COUNTER or TIMER.

Counter increments on T0 pin change state.

Counter0 Mode2 is 8-bit autoreloadable counter.

Author

Michael Golovanov

Macro Definition Documentation

counter0_mode2_close_gate

#define counter0_mode2_close_gate

(

)

(bit_set(TMOD, SBIT3))

Close counter0 gate.

Closing gate stop counter0.

counter0_mode2_disable_P35_output

#define counter0_mode2_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_mode2_enable_P35_output

#define counter0_mode2_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_mode2_get_value

#define counter0_mode2_get_value

(

)

(TL0)

get counter0 value in mode2

Returns

uint8_t counter value

counter0_mode2_init

#define counter0_mode2_init

(

)

Value:

do {                                            \
    enable_mcu_interrupts();                    \
    enable_timer0_interrupt();                  \
                                                \
    TMOD &= 0xF0;                               \
    TMOD |= 0x06;                               \
                                                \
    TF0 = 0;                                    \
    TR0 = 0;                                    \
} while(0)

Initialize mode2 for counter0.

Enable counter0 interrupt and set mode2.

Mode2 is configured as setting TMOD lowest 4 bytes:

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

Attention

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

counter0_mode2_open_gate

#define counter0_mode2_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_mode2_set_value

#define counter0_mode2_set_value

(

value

)

Value:

do {                                            \
    static_assert(value <= 0xff, "value is too large"); \
    TH0 = value;                                \
} while(0)

set counter0 value in mode2

Call this method before counter0 started.

Parameters

value

uint8_t counter value to set

counter0_mode2_start

#define counter0_mode2_start

(

value

)

Value:

 do {                                           \
    static_assert(value <= 0xff, "value is too large"); \
                                                \
    TH0 = (uint8_t) value;                      \
                                                \
    TF0 = 0;                                    \
    TR0 = 1;                                    \
 } while(0)

Starts Counter 0 in Mode 2 with a specified initial value.

Loads the initial 8-bit value into Counter 0 registers and starts the counter.

Attention

Before calling this function, counter0_mode2_init() should be called.

Parameters

value

8-bit unsigned integer specifying the initial counter count

counter0_mode2_stop

#define counter0_mode2_stop

(

)

Value:

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

Stop counter0.

Stop count T0 pin state changes. Before stop counter0_mode2_start should be called.

is_counter0_mode2_gate_opened

#define is_counter0_mode2_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_mode2_P35_output_enabled

#define is_counter0_mode2_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_mode2_started

#define is_counter0_mode2_started

(

)

(TR0 == 1 && (is_counter0_mode2_gate_opened() || INT0 == 1) )

Get counter0 mode2 started status.

Returns

bool true if started otherwise false