Manual
Table Of Contents
- Features
- Description
- Architectural Overview
- General-purpose Register File
- ALU – Arithmetic Logic Unit
- In-System Programmable Flash Program Memory
- EEPROM Data Memory
- SRAM Data Memory
- Program and Data Addressing Modes
- Register Direct, Single Register Rd
- Register Direct, Two Registers Rd and Rr
- I/O Direct
- Data Direct
- Data Indirect with Displacement
- Data Indirect
- Data Indirect with Pre- decrement
- Data Indirect with Post- increment
- Constant Addressing Using the LPM Instruction
- Indirect Program Addressing, IJMP and ICALL
- Relative Program Addressing, RJMP and RCALL
- Memory Access and Instruction Execution Timing
- I/O Memory
- Reset and Interrupt Handling
- Reset Sources
- Power-on Reset
- External Reset
- Watchdog Reset
- MCU Status Register – MCUSR
- Interrupt Handling
- General Interrupt Mask Register – GIMSK
- General Interrupt Flag Register – GIFR
- Timer/Counter Interrupt Mask Register – TIMSK
- Timer/Counter Interrupt FLAG Register – TIFR
- External Interrupt
- Interrupt Response Time
- MCU Control Register – MCUCR
- Sleep Modes
- Timer/Counter
- Watchdog Timer
- EEPROM Read/Write Access
- I/O Port B
- Memory Programming
- Electrical Characteristics
- Typical Characteristics
- AT90S2323/2343 Register Summary
- Ordering Information
- Packaging Information

41
AT90S/LS2323/2343
1004D–09/01
Note: a = address high bits
b = address low bits
i = data in
o = data out
x = don’t care
1 = Lock Bit1
2 = Lock Bit2
F = FSTRT Fuse
R = RCEN Fuse
S = SPIEN Fuse
Read Fuse
and Lock Bits
(AT90S/
LS2323)
PB0
PB1
PB2
0_0000_0100_00
0_0100_1100_00
x_xxxx_xxxx_xx
0_0000_0000_00
0_0111_1000_00
x_xxxx_xxxx_xx
0_0000_0000_00
0_0111_1100_00
1_2Sxx_xxRx_xx
Reading 1, 2, S, R = “0” means
the Fuse/Lock bit is
programmed.
Read Fuse
and Lock Bits
(AT90S/
LS2343)
PB0
PB1
PB2
0_0000_0100_00
0_0100_1100_00
x_xxxx_xxxx_xx
0_0000_0000_00
0_0111_1000_00
x_xxxx_xxxx_xx
0_0000_0000_00
0_0111_1100_00
1_2Sxx_xxRx_xx
Reading 1, 2, S, R = “0” means
the Fuse/Lock bit is
programmed.
Read
Signature
Bytes
PB0
PB1
PB2
0_0000_1000_00
0_0100_1100_00
x_xxxx_xxxx_xx
0_0000_00bb_00
0_0000_1100_00
x_xxxx_xxxx_xx
0_0000_0000_00
0_0110_1000_00
x_xxxx_xxxx_xx
0_0000_0000_00
0_0110_1100_00
o_oooo_ooox_xx
Repeat Instr.2 - Instr.4 for each
signature byte address.
Table 16. High-voltage Serial Programming Instruction Set (Continued)
Instruction
Instruction Format
Operation RemarksInstr.1 Instr.2 Instr.3 Instr.4










