HT46R14
Mode
Initial Reset
External Interrupt 0
External Interrupt 1
Comparator 0 interrupt
Timer/Event Counter 0 Overflow
Timer/Event Counter 1 Overflow
A/D Converter Interrupt
Skip
Loading PCL
Jump, Call Branch
Return from Subroutine
*11
#11
S11
*10
#10
S10
*9
#9
S9
*8
#8
S8
Program Counter
*11
0
0
0
0
0
0
0
*10
0
0
0
0
0
0
0
*9
0
0
0
0
0
0
0
*8
0
0
0
0
0
0
0
*7
0
0
0
0
0
0
0
*6
0
0
0
0
0
0
0
*5
0
0
0
0
0
0
0
*4
0
0
0
0
1
1
1
*3
0
0
1
1
0
0
1
*2
0
1
0
1
0
1
0
*1
0
0
0
0
0
0
0
*0
0
0
0
0
0
0
0
Program Counter+2
@7
#7
S7
@6
#6
S6
@5
#5
S5
@4
#4
S4
@3
#3
S3
@2
#2
S2
@1
#1
S1
@0
#0
S0
Program Counter
Note:
*11~*0: Program counter bits
#11~#0: Instruction code bits
S11~S0: Stack register bits
@7~@0: PCL bits
·
Location 00CH
The conditional skip is activated by instructions. Once
the condition is met, the next instruction, fetched during
the current instruction execution, is discarded and a
dummy cycle replaces it to get the proper instruction.
Otherwise proceed with the next instruction.
The lower byte of the program counter (PCL) is a read-
able and writeable register (06H). Moving data into the
PCL performs a short jump. The destination will be
within 256 locations. When a control transfer takes
place, an additional dummy cycle is required.
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
4096´15 bits, addressed by the program counter and ta-
ble pointer.
Certain locations in the program memory are reserved
for special usage:
·
Location 000H
Location 00CH is reserved for the Comparator 0 inter-
rupt service program. If the Comparator 0 output pin is
activated, and if the interrupt is enable and the stack is
not full, the program begins execution at location
00CH.
·
Location 010H
Location 010H is reserved for the Timer/Event Coun-
ter 0 interrupt service program. If a timer interrupt re-
sults from a Timer/Event Counter 0 overflow, and if the
interrupt is enabled and the stack is not full, the pro-
gram begins execution at location 010H.
·
Location 014H
Location 014H is reserved for the Timer/Event Coun-
ter 1 interrupt service program. If a timer interrupt re-
sults from a Timer/Event Counter 1 overflow, and if the
interrupt is enabled and the stack is not full, the pro-
gram begins execution at location 014H.
·
Location 018H
Location 000H is reserved for program initialization.
After chip reset, the program always begins execution
at location 000H.
·
Location 004H
Location 018H is reserved for the A/D converter inter-
rupt service program. If an A/D converter interrupt re-
sults from an end of A/D conversion, and if the
interrupt is enabled and the stack is not full, the pro-
gram begins execution at location 018H.
·
Table location
Location 004H is reserved for the external interrupt 0
service program. If the INT0 input pin is activated, the
interrupt is enabled and the stack is not full, the pro-
gram begins execution at location 004H.
·
Location 008H
Location 008H is reserved for the external Interrupt 1
service program. If the INT1 input pin is activated, the
interrupt is enabled and the stack is not full, the pro-
gram begins execution at location 008H.
Rev. 1.00
6
Any location in the PROM space can be used as
look-up tables. The instructions
²TABRDC
[m]² (the
current page, 1 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). Only the destination
of the lower-order byte in the table is well-defined, the
other bits of the table word are transferred to the lower
portion of TBLH, and the remaining 1 bit is read as
²0².
November 1, 2005
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
