AT90S8535-8AI Atmel, AT90S8535-8AI Datasheet - Page 10

• Manufacturer Part Number: AT90S8535-8AI
• Description: IC MCU 8K 8MHZ A/D IT 44TQFP
• Manufacturer: Atmel
• Series: AVR® 90Sr

Specifications of AT90S8535-8AI

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 8KB (4K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 6 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

X-register, Y-register and Z-
register
ALU – Arithmetic Logic
Unit
In-System Programmable
Flash Program Memory
10
AT90S/LS8535
The registers R26..R31 have some added functions to their general-purpose usage.
These registers are address pointers for indirect addressing of the Data Space. The
three indirect address registers, X, Y, and Z, are defined in Figure 7.
Figure 7. X-, Y-, and Z-register
In the different addressing modes, these address registers have functions as fixed dis-
placement, automatic increment and decrement (see the descriptions for the different
instructions).
The high-performance AVR ALU operates in direct connection with all the 32 general-
purpose working registers. Within a single clock cycle, ALU operations between regis-
ters in the register file are executed. The ALU operations are divided into three main
categories: arithmetic, logical and bit functions.
The AT90S8535 contains 8K bytes On-chip, In-System Programmable Flash memory
for program storage. Since all instructions are 16- or 32-bit words, the Flash is orga-
nized as 4K x 16. The Flash memory has an endurance of at least 1000 write/erase
cycles. The AT90S8535 Program Counter (PC) is 12 bits wide, thus addressing the
4096 program memory addresses.
See page 99 for a detailed description on Flash data downloading.
See page 12 for the different program memory addressing modes.
X-register
Y-register
Z-register
15
7
15
7
15
7
R27 ($1B)
R29 ($1D)
R31 ($1F)
0
0
0
7
7
7
R28 ($1C)
R30 ($1E)
R26 ($1A)
1041H–11/01
0
0
0
0
0
0