w78l365a Winbond Electronics Corp America, w78l365a Datasheet - Page 6

• Manufacturer Part Number: w78l365a
• Description: 8-bit Microcontroller
• Manufacturer: Winbond Electronics Corp America

5.
The W78L365A architecture consists of a core controller surrounded by various registers, four general
purpose I/O ports, one special purpose programmable 4-bits I/O port, 256+1K bytes of RAM, three
timer/counters, a serial port. The processor supports 111 different opcodes and references both a 64K
program address space and a 64K data storage space.
5.1
The internal data RAM in the W78L365A is 256+1K bytes. It is divided into two banks: 256 bytes of
scratchpad RAM and 1K bytes of AUX-RAM. These RAMs are addressed by different ways.
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•
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Example:
CHPENR
CHPCON
XRAMAH
MOV
MOV
ORL
MOV
MOV
MOV
MOV
MOVX
MOV
MOV
MOVX
MOV
MOV
MOVX
MOV
MOVX
RAM 0H−7FH can be addressed directly and indirectly as the same as in 8051. Address pointers
are R0 and R1 of the selected register bank.
RAM 80H−FFH can only be addressed indirectly as the same as in 8051. Address pointers are
R0, R1 of the selected registers bank.
AUX-RAM 0H−3FFH is addressed indirectly as the same way to access external data memory
with the MOVX instruction. Address pointer are R0 and R1 of the selected register bank and
DPTR register. An access to external data memory locations higher than 3FFH will be performed
with the MOVX instruction in the same way as in the 8051. The AUX-RAM is enable after a reset.
Setting the bit 4 in CHPCON register will enable the access to AUX-RAM. When executing from
internal program memory, an access to AUX-RAM will not affect the Ports P0, P2, WR and RD .
FUNCTIONAL DESCRIPTION
RAM
XRAMAH, #01H
XRAMAH, #02H
R1, #FFH
CHPENR , #87H
CHPENR, #59H
CHPCON, #00010000B ; enable AUX-RAM
CHPENR, #00H
R0, #23H
A, #55H
@R0, A
DPTR, #0134H
A, #78H
DPTR, #7FFFH
A, @R1
@DPTR,A
A, @DPRT
REG
REG
REG
A1H
F6H
BFH
; Write 78h data to 0134h AUX-RAM address.
; Read data from the external 7FFFh address SRAM
; internal high address
; Write 55h data to 0123h AUX-RAM address.
; Read data from 02FFh AUX-RAM address.
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W78LE365/W78L365A
Publication Release Date: April 28, 2008
Revision A8