NT68F62 Datasheet, PDF (9/57 Pages) List of Unclassifed Manufacturers – 8-Bit Microcontroller for Monitor (32K Flash MTP Type)

NT68F62
3. RAM: 512 X 8 bits
The built-in 512 X 8-bit SRAM is used for data memory and stack area. The RAM addressing range is from $0080 to $027F.
The contents of RAM are undetermined at power-up and are not affected by system reset. Software programmers can
allocate stack area in the RAM by setting stack pointer register (S). Since the 6502 default stack pointer is $01FF,
programmers must set S register to FFH when starting the program.
as; LDX #$FF
TXS
$0000
$003E
$0080
$01FF
$027F
$0280
System Registers
Unused
RAM
( 512 Bytes )
Unused
stack pointer
$77FF
$7800
( 2 K Bytes )
$7FFA
$7FFB
$7FFC
$7FFD
$7FFE
$7FFF
$8000
( 32 K Bytes )
Boot
ROM
NMI-L
NMI-H
RST-L
RST-H
IRQ-L
IRQ-H
Flash
Memory
NMI vector
RESET vector
IRQ vector
$FFFA
$FFFB
$FFFC
$FFFD
$FFFE
$FFFF
NMI-L
NMI-H
RST-L
RST-H
IRQ-L
IRQ-H
NMI vector
RESET vector
IRQ vector
4.1. BootROM: 2K X 8 bits
NT68F62 Provides 2K bytes of Boot-ROM for ISP. The memory space is from $7800 to $7FFF. The addresses, from $7FFA
to $7FFF, are reserved for the 6502 CPU vector.
4.2. Flash memory: 32K X 8 bits
NT68F62 provides 32K flash memory space for programming. The flash memory space is located from $8000 to $FFFF.
The addresses, from $FFFA to $FFFF, are reserved for the 6502 CPU vectors, thus users must arrange them by
themselves. This flash memory can be progammed repeatly at limited times to guarantee its performance.
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