at90ls8535-8mi ATMEL Corporation, at90ls8535-8mi Datasheet - Page 7

• Manufacturer Part Number: at90ls8535-8mi
• Description: 8-bit Microcontroller With 8k Bytes In-system Programmable Flash
• Manufacturer: ATMEL Corporation

Architectural
Overview
1041H–11/01
The fast-access register file concept contains 32 x 8-bit general-purpose working regis-
ters with a single clock cycle access time. This means that during one single clock cycle,
one Arithmetic Logic Unit (ALU) operation is executed. Two operands are output from
the register file, the operation is executed and the result is stored back in the register file
– in one clock cycle.
Six of the 32 registers can be used as three 16-bit indirect address register pointers for
Data Space addressing, enabling efficient address calculations. One of the three
address pointers is also used as the address pointer for the constant table look-up func-
tion. These added function registers are the 16-bit X-register, Y-register, and Z-register.
Figure 4. The AT90S8535 AVR RISC Architecture
The ALU supports arithmetic and logic functions between registers or between a con-
stant and a register. Single register operations are also executed in the ALU. Figure 4
shows the AT90S8535 AVR RISC microcontroller architecture.
In addition to the register operation, the conventional memory addressing modes can be
used on the register file as well. This is enabled by the fact that the register file is
Control Lines
Instruction
Instruction
Program
4K X 16
Register
Decoder
Memory
Program
Counter
and Control
Registrers
EEPROM
I/O Lines
Purpose
General
512 x 8
512 x 8
Data Bus 8-bit
SRAM
Status
32 x 8
Data
ALU
32
AT90S/LS8535
Analog to Digital
Timer/Counter
Timer/Counter
Timer/Counter
Comparator
with PWM
with PWM
Watchdog
Converter
Interrupt
Analog
UART
Serial
16-bit
Timer
8-bit
8-bit
Unit
Unit
SPI
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