HT48R063B/064B/065B/066B
Table Read Program Example:
tempreg1 db
tempreg2 db
?
?
; temporary register #1
; temporary register #2
:
:
mov a,06h
; initialise table pointer - note that this address
; is referenced
mov tblp,a
; to the last page or present page
:
:
tabrdl
tempreg1
tempreg2
; transfers value in table referenced by table pointer
; to tempregl
; data at prog. memory address ²306H² transferred to
; tempreg1 and TBLH
dec tblp
tabrdl
; reduce value of table pointer by one
; transfers value in table referenced by table pointer
; to tempreg2
; data at prog.memory address ²305H² transferred to
; tempreg2 and TBLH
; in this example the data ²1AH² is transferred to
; tempreg1 and data ²0FH² to register tempreg2
; the value ²00H² will be transferred to the high byte
; register TBLH
:
:
org 300h
; sets initial address of last page
dc 00Ah, 00Bh, 00Ch, 00Dh, 00Eh, 00Fh, 01Ah, 01Bh
:
:
Data Memory
The Data Memory is a volatile area of 8-bit wide RAM
internal memory and is the location where temporary in-
formation is stored.
The two sections of Data Memory, the Special Purpose
and General Purpose Data Memory are located at con-
secutive locations. All are implemented in RAM and are 8
bits wide but the length of each memory section is dic-
tated by the type of microcontroller chosen. The start ad-
dress of the Data Memory for all devices is the address
²00H².
Structure
Divided into two sections, the first of these is an area of
RAM where special function registers are located. These
registers have fixed locations and are necessary for cor-
rect operation of the device. Many of these registers can
be read from and written to directly under program con-
trol, however, some remain protected from user manipu-
lation. The second area of Data Memory is reserved for
general purpose use. All locations within this area are
read and write accessible under program control.
All microcontroller programs require an area of
read/write memory where temporary data can be stored
and retrieved for use later. It is this area of RAM memory
that is known as General Purpose Data Memory. This
area of Data Memory is fully accessible by the user pro-
gram for both read and write operations. By using the
²SET [m].i² and ²CLR [m].i² instructions individual bits
can be set or reset under program control giving the
user a large range of flexibility for bit manipulation in the
Data Memory.
Device
Capacity
Banks
HT48R063B
HT48R064B
64´8
¾
For some devices, the Data Memory is subdivided into
two banks, which are selected using a Bank Pointer.
Only data in Bank 0 can be directly addressed, data in
Bank 1 must be indirectly addressed.
HT48R065B
HT48R066B
96´8
¾
¾
128´8
Rev. 1.00
19
April 7, 2011
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
