atmega161-4pi ATMEL Corporation, atmega161-4pi Datasheet - Page 17

• Manufacturer Part Number: atmega161-4pi
• Description: 8-bit Microcontroller With 16k Bytes Of In-system Programmable Flash
• Manufacturer: ATMEL Corporation

Relative Program Addressing,
RJMP and RCALL
Direct Program Addressing,
JMP and CALL
Memory Access Times
and Instruction
Execution Timing
1228D–AVR–02/07
Program execution continues at address contained by the Z-register (i.e., the PC is
loaded with the contents of the Z-register).
Figure 19. Relative Program Memory Addressing
Program execution continues at address PC + k + 1. The relative address k is -2048 to
2047.
Figure 20. Direct Program Addressing
Program execution continues at the address immediate in the instruction words.
This section describes the general access timing concepts for instruction execution and
internal memory access.
The AVR CPU is driven by the System Clock Ø, directly generated from the external
clock crystal for the chip. No internal clock division is used.
Figure 21 shows the parallel instruction fetches and instruction executions enabled by
the Harvard architecture and the fast-access Register File concept. This is the basic
pipelining concept to obtain up to 1 MIPS per MHz with the corresponding unique results
for functions per cost, functions per clocks and functions per power unit.
15
15
OP
31
15
12 11
OP
PC
16 LSBs
k
21 20
0
0
16
0
PROGRAM MEMORY
PROGRAM MEMORY
ATmega161(L)
$0000
$1FFF
$000
$1FFF
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