HT46R92 datasheet(35/61 Pages) HOLTEK

35 / 61 page

HT46R92

Rev. 1.10

November 5, 2008

Timer/Event Counter Interrupt

For a Timer/Event Counter interrupt to occur, the global

interrupt enable bit, EMI , and the corresponding timer

interrupt enable bit, ETI in the INTC0 register must first

be set. An actual Timer/Event Counter interrupt will take

place when the Timer/Event Counter interrupt request

flag, TF in INTC0, is set, a situation that will occur when

the relevant Timer/Event Counter overflows. When the

interrupt is enabled, the stack is not full and a

Timer/Event Counter overflow occurs, a subroutine call

to the timer interrupt vector at location 08H will take

place for Timer/Event Counter. When the interrupt is

serviced, the timer interrupt request flag, TF, will be au-

tomatically reset and the EMI bit will be automatically

cleared to disable other interrupts.

Time Base Interrupt

For a Time Base interrupt to occur, the global interrupt

enable bit, EMI, in the INTC0 register, and the Time

Base interrupt enable bit, ETBI, in the INTC0 register

must first be set. An actual Time Base interrupt will take

place when the Time Base request flag, TBF in INTC0 is

set, a situation that will occur when the Time Base over-

flows. When the interrupt is enabled, the stack is not full,

and a Time Base overflow occurs, a subroutine call to

the Time Base vector location at 0CH will take place.

When the interrupt is serviced, the Time Base interrupt

request flag, TBF, will be automatically reset and the

EMI bit will be automatically cleared to disable other in-

terrupts.

A/D Interrupt

For an A/D interrupt to occur, the global interrupt enable

bit, EMI, and the corresponding interrupt enable bit,

EADI, must be first set. An actual A/D interrupt will take

place when the A/D converter request flag, ADF in the

INTC1 register is set, a situation that will occur when an

A/D conversion process has completed. When the inter-

rupt is enabled, the stack is not full and an A/D conver-

sion process finishes execution, a subroutine call to the

A/D interrupt vector at location 10H, will take place.

When the interrupt is serviced, the A/D interrupt request

flag, ADF, will be automatically reset and the EMI bit will

be automatically cleared to disable other interrupts.

Programming Considerations

By disabling the interrupt enable bits, a requested inter-

rupt can be prevented from being serviced, however,

once an interrupt request flag is set, it will remain in this

condition in the INTC0 or INTC1 register until the corre-

sponding interrupt is serviced or until the request flag is

cleared by a software instruction.

It is recommended that programs do not use the

²CALL

subroutine

² instruction within the interrupt subroutine.

Interrupts often occur in an unpredictable manner or

need to be serviced immediately in some applications. If

only one stack is left and the interrupt is not well con-

trolled, the original control sequence will be damaged

once a

²CALL subroutine² is executed in the interrupt

subroutine.

All of these interrupts have the capability of waking up

the processor when in the Power Down Mode.

Only the Program Counter is pushed onto the stack. If

the contents of the register or status register are altered

by the interrupt service program, which may corrupt the

desired control sequence, then the contents should be

saved in advance.

C l o c k S o u r c e

C o n f i g u r a t i o n

O p t i o n

f S Y S / 4

W D T O s c i l l a t o r

R T C O s c i l l a t o r

8 - S t a g e P r e s c a l e r

( 1 / 2 ~ 1 / 2 5 6 )

f S

T B 0 ~ T B 2

¸ 1 6

T i m e B a s e I n t e r r u p t

( f S / 3 2 ~ f S / 4 0 9 6 )

T i m e B a s e C l o c k S o u r c e S e l e c t

Time Base Interrupt

HT46R92 датащи(PDF) 35 Page - Holtek Semiconductor Inc

HT46R92 датащи(HTML) 35 Page - Holtek Semiconductor Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61

датащи скачать

ссылки URL