HT48RU80/HT48CU80
8192´16 bits´2 banks, addressed by the Program
Counter and table pointer.
The BP register bit5 is used to select the ROM bank.
When the BP¢s bit5=0, the ROM bank 0 ranges from
0000H to 1FFFH. When the BP¢s bit5=1, the ROM
bank1 ranges from 2000H to 3FFFH.
The
²CALL²
and
²JMP²
instruction provide only 13 bits
of address to allow branching within any 8K program
memory bank. When doing a
²CALL²
or
²JMP²
instruc-
tion, the upper 1 bit of the address is provided by BP5.
When doing a
²CALL²
or
²JMP²
instruction, user must
ensure that the bank select bit is programmed so that
the desired program memory bank is addressed. If a re-
turn from
²CALL²
instruction (or interrupt) is executed,
the entire 14-bit Program Counter is popped off the
stack.
Certain locations in the program memory are reserved
for special usage:
0 0 0 H
0 0 4 H
0 0 8 H
0 0 C H
0 1 0 H
0 1 4 H
0 1 8 H
n 0 0 H
D e v ic e In itia liz a tio n P r o g r a m
E x te r n a l In te r r u p t 0 S u b r o u tin e
T im e r /E v e n t C o u n te r 0
In te r r u p t S u b r o u tin e
T im e r /E v e n t C o u n te r 1
In te r r u p t S u b r o u tin e
E x te r n a l In te r r u p t 1 S u b r o u tin e
U A R T In te r r u p t S u b r o u tin e
T im e r /E v e n t C o u n te r 2
In te r r u p t S u b r o u tin e
P ro g ra m
M e m o ry
·
Location 000H
This area is reserved for program initialization. After a
chip reset, the program always begins execution at lo-
cation 000H.
·
Location 004H
This area is reserved for the external interrupt 0 ser-
vice program. If the INT0 interrupt pin is activated, the
interrupt enabled and the stack is not full, the program
begins execution at location 004H.
·
Location 008H
This area is reserved for the Timer/Event Counter 0 in-
terrupt service program. If a timer interrupt results from a
Timer/Event Counter 0 overflow, and if the interrupt is
enabled and the stack is not full, the program begins ex-
ecution at location 008H.
·
Location 00CH
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.
·
Location 010H
This area is reserved for the external interrupt 1 ser-
vice program. If the INT1 interrupt pin is activated, the
interrupt enabled and the stack is not full, the program
begins execution at location 010H.
·
Location 014H
This area is reserved for the UART interrupt service
program. If a UART interrupt results from a UART TX
or RX, and the interrupt is enabled and the stack is not
full, the program begins execution at location 014H.
·
Location 018H
n F F H
L o o k - u p T a b le ( 2 5 6 w o r d s )
1 F 0 0 H
1 F F F H
2 0 0 0 H
L o o k - u p T a b le ( 2 5 6 w o r d s )
This location is reserved for the Timer/Event Counter
2 interrupt service program. If a timer interrupt results
from a Timer/Event Counter 2 overflow, and the inter-
rupt is enabled and the stack is not full, the program
begins execution at location 018H.
·
Table location
3 F F F H
1 6 b its
N o te : n ra n g e s fro m
0 to 3 F
Program Memory
Instruction
TABRDC [m]
TABRDL [m]
Any location in the program memory can be used as
look-up tables. The instructions
²TABRDC
[m]² (the
current page, one page=256 words) and
²TABRDL
[m]² (the last page) transfer the contents of the
lower-order byte to the specified data memory, and
the higher-order byte to TBLH (08H). The Table
Table Location
*13
P13
1
*12
P12
1
*11
P11
1
*10
P10
1
*9
P9
1
*8
P8
1
*7
@7
@7
*6
@6
@6
*5
@5
@5
*4
@4
@4
*3
@3
@3
*2
@2
@2
*1
@1
@1
*0
@0
@0
Table Location
Note: *13~*0: Table location bits
@7~@0: Table pointer bits
Rev. 1.00
8
April 12, 2006
P13~P8: Current program counter bits
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
