Rainbow Electronics AT90S8515 - Manual (Page 11)

11
AT90S8515
0841G–09/01
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).
ALU – Arithmetic Logic
Unit 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.
In-System Programmable
Flash Program Memory The AT90S8515 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 organized as
4K x 16. The Flash memory has an endurance of at least 1000 write/erase cycles. The
AT90S8515 Program Counter (PC) is 12 bits wide, thus addressing the 4096 program
memory addresses.
See page 86 for a detailed description of Flash data downloading.
See page 13 for the different program memory addressing modes.