46
AT94KAL Series FPSLIC
Rev. 1138G–FPSLI–11/03
Figure 29.
The Parallel Instruction Fetches and Instruction Executions
Figure 30 shows the internal timing concept for the register file. In a single clock cycle an ALU
operation using two register operands is executed, and the result is stored back to the destina-
tion register.
Figure 30.
Single Cycle ALU Operation
The internal data SRAM access is performed in two system clock cycles as described in
Figure 31.
Figure 31.
On-chip Data SRAM Access Cycles
AVR CLK
1st Instruction Fetch
1st Instruction Execute
2nd Instruction Fetch
2nd Instruction Execute
3rd Instruction Fetch
3rd Instruction Execute
4th Instruction Fetch
T1
T2
T3
T4
AVR CLK
Total ExecutionTime
Register Operands Fetch
ALU Operation Execute
Result Write Back
T1
T2
T3
T4
AVR CLK
WR
RD
Data
Data
Address
Address
T1
T2
T3
T4
Prev. Address
Read
Wr
ite