HT48R02 datasheet(7/38 Pages) HOLTEK

7 / 38 page

HT48R01/HT48R02/HT48R03

Rev. 1.00

December 20, 2006

Program Memory

- ROM

The program memory is used to store the program in-

structions which are to be executed. It also contains

data, table, and interrupt entries, and is organized into

1024

´14 bits for the HT48R01, 2048´14 bits for the

HT48R02 or 4096

´15 bits for the HT48R03, addressed

by the program counter and table pointer.

Certain locations in the program memory are reserved

for special usage:

· Location 000H

This area is reserved for program initialization. After

chip reset, the program always begins execution at lo-

cation 000H.

· Location 004H

This area is reserved for the external interrupt service

program. If the INT input pin is activated, the interrupt

is enabled and the stack is not full, the program begins

execution at location 004H.

· Location 008H

This location is reserved for the Timer/Event Counter

0 interrupt service program. If a timer interrupt results

from a Timer/Event Counter 0 overflow, and the inter-

rupt is enabled and the stack is not full, the program

begins execution at location 008H.

· Location 00CH (HT48R02/HT48R03 only)

This location is reserved for the Timer/Event Counter

1 interrupt service program. If a timer interrupt results

from a Timer/Event Counter 1 overflow, and the inter-

rupt is enabled and the stack is not full, the program

begins execution at location 00CH.

· Table location

Any location in the program memory can be used as

look-up tables. The instructions

²TABRDC [m]² (the

current page) and

²TABRDL [m]² (the last page) trans-

fer the contents of the lower-order byte to the speci-

fied data memory, and the higher-order byte to TBLH

(08H). Only the destination of the lower-order byte in

the table is well-defined, the other bits of the table

D e v i c e I n i t i a l i z a t i o n P r o g r a m

E x t e r n a l I n t e r r u p t S u b r o u t i n e

T i m e r / E v e n t C o u n t e r 0 I n t e r r u p t S u b r o u t i n e

L o o k - u p T a b l e ( 2 5 6 w o r d s )

N o t e : n r a n g e s f r o m 0 t o 3

D e v i c e I n i t i a l i z a t i o n P r o g r a m

E x t e r n a l I n t e r r u p t S u b r o u t i n e

T i m e r / E v e n t C o u n t e r 0 I n t e r r u p t S u b r o u t i n e

L o o k - u p T a b l e ( 2 5 6 w o r d s )

N o t e : n r a n g e s f r o m 0 t o 7

T i m e r / E v e n t C o u n t e r 1 I n t e r r u p t S u b r o u t i n e

n 0 0 H

n F F H

D e v i c e I n i t i a l i z a t i o n P r o g r a m

E x t e r n a l I n t e r r u p t S u b r o u t i n e

T i m e r / E v e n t C o u n t e r 0 I n t e r r u p t S u b r o u t i n e

L o o k - u p T a b l e ( 2 5 6 w o r d s )

N o t e : n r a n g e s f r o m 0 t o F

0 0 0 H

0 0 4 H

0 0 8 H

0 0 C H

F F F H

F 0 0 H

T i m e r / E v e n t C o u n t e r 1 I n t e r r u p t S u b r o u t i n e

H T 4 8 R 0 1

H T 4 8 R 0 2

H T 4 8 R 0 3

1 4 b i t s

P r o g r a m

M e m o r y

1 4 b i t s

1 5 b i t s

P r o g r a m

M e m o r y

n F F H

3 F F H

3 0 0 H

0 0 0 H

0 0 4 H

0 0 8 H

n 0 0 H

P r o g r a m

M e m o r y

n 0 0 H

n F F H

0 0 0 H

0 0 4 H

0 0 8 H

0 0 C H

7 F F H

7 0 0 H

Program Memory

Instruction

Table Location

*11

*10

TABRDC [m]

P11

P10

TABRDL [m]

1111

Table Location

Note: *11~*0: Table location bits

P11~P8: Current program counter bits

@7~@0: Table pointer bits

For the HT48R01, the table address location is 10 bits, i.e. from *9~*0

For the HT48R02, the table address location is 11 bits, i.e. from *10~*0

For the HT48R03, the table address location is 12 bits, i.e. from *11~*0

HT48R02 Datasheet(PDF) 7 Page - Holtek Semiconductor Inc

HT48R02 Datasheet(HTML) 7 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

Datasheet Download

Link URL