EM73962A
4-BIT MICROCONTROLLER
User's program and fixed data are stored in the program ROM. User's program is according the PC value
to send next executed instruction code.
The 16Kx8 bits program ROM can be divided into 4 banks. There are 4Kx8 bits in each bank.
The bank of the program ROM is selected by P3(1..0). The program counter is a 13-bit binary counter. The PC
and P3 are initialized to "0" during reset.
When P3(1..0)=00B, the bank0 and bank1 of program ROM will be selected. P3(1..0)=01B, the the bank0 and
bank2 will be selected. P3(1..0)=01B, the bank0 and bank3 will be selected.
Address
0000h
P3=xx00B
Bank0
P3=xx01B
Bank0
P3=xx10b
Bank0
:
:
0FFFh
1000h
:
:
Bank1
Bank2
Bank3
1FFFh
PROGRAM EXAMPLE:
BANK 0
START:
:
:
:
LDIA #00H
OUTA P3
; set program ROM to bank1
; set program ROM to bank2
; set program ROM to bank3
B
:
XA1
XA :
XB :
:
:
LDIA #01H
OUTA P3
B
:
XB1
:
:
LDIA #02H
OUTA P3
B
:
XC1
XC :
XD :
:
:
B
:
XD
:
:
; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
BANK
1
XA1 :
:
:
B
:
XA
XA2 :
:
* This specification are subject to be changed without notice.
10.8.2001
4
ELAN [ ELAN MICROELECTRONICS CORP ]
