R5F21256SNFP#U0 Renesas Electronics America, R5F21256SNFP#U0 Datasheet - Page 272

• Manufacturer Part Number: R5F21256SNFP#U0
• Description: IC R8C MCU FLASH 32K 52LQFP
• Manufacturer: Renesas Electronics America
• Series: R8C/2x/25r

Specifications of R5F21256SNFP#U0

• Core Processor: R8C
• Core Size: 16/32-Bit
• Speed: 20MHz
• Connectivity: I²C, LIN, SIO, SSU, UART/USART
• Peripherals: POR, Voltage Detect, WDT
• Number Of I /o: 41
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 2.2 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 52-LQFP
• For Use With: R0K521256S000BE - KIT EVAL STARTER FOR R8C/25
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

Rev.2.00 Oct 17, 2005
REJ09B0001-0200
5.3 Interrupt Sequence
The interrupt sequence — the operations performed from the instant an interrupt is accepted to the instant
the interrupt routine is executed — is described here.
If an interrupt occurs during execution of an instruction, the processor determines its priority when the
execution of the instruction is completed and transfers control to the interrupt sequence from the next cycle.
If an interrupt occurs during execution of the SMOVB, SMOVF, SSTR, or RMPA instruction, the processor
temporarily suspends the instruction being executed and transfers control to the interrupt sequence.
In the interrupt sequence, the processor carries out the operations listed below. Figure 5.3.1 shows the
interrupt sequence execution time.
After the interrupt sequence is completed, the processor resumes executing instructions from the starting
address of the interrupt routine.
Note 1: This register cannot be accessed by the user.
Chapter 5
Figure 5.3.1 Interrupt Sequence Executing Time
(1) The CPU obtains the interrupt information (the interrupt number and interrupt request level) by reading
(2) The FLG register is saved as it was immediately before the start of the interrupt sequence in a tempo-
(3) The I flag, the D flag, and the U flag in the FLG register are set as follows:
(4) The contents of the temporary register
(5) The PC is saved in the stack area.
(6) The interrupt priority level of the accepted instruction is set in IPL.
(7) The first address of the interrupt routine set to the interrupt vector is set in the PC.
A d d r e s s b u s
C P U c l o c k
• The I flag is cleared to 0 (interrupts disabled)
• The D flag is cleared to 0 (single-step interrupt disabled)
•The U flag is cleared to 0 (ISP specified)
However, the U flag status does not change when the INT instruction for software interrupt numbers 32 to
63 is executed.
D a t a b u s
address 00000
issued).
rary register
R D
W R
1
N o t e : U n d e f i n e d p a r t s d i f f e r a c c o r d i n g t o t h e s t a t e s o f t h e q u e u e b u f f e r .
Interrupts
I f t h e q u e u e b u f f e r i s i n a s t a t e w h e r e a n i n s t r u c t i o n c a n b e a c c e p t e d , a r e a d
c y c l e i s g e n e r a t e d .
1
2
A d d r e s s
0 0 0 0 0
within the CPU.
i n f o r m a t i o n
16
I n t e r r u p t
page 252 of 263
1 6
. Then, the IR bit corresponding to the interrupt is set to 0 (interrupt not requested
3
4
5
U n d e f i n e d
U n d e f i n e d
Undefined
6
7
1
are saved within the CPU in the stack area.
8
S P - 2
9
c o n t e n t s
S P - 2
S P - 1
1 0
contents
SP-1
SP-4
11
c o n t e n t s
S P - 4
1 2
SP-3
contents
SP-3
13
V E C
1 4
c o n t e n t s
V E C
15
V E C + 1
c o n t e n t s
V E C + 1
1 6
5.3 Interrupt Sequence
1 7
V E C + 2
c o n t e n t s
V E C + 2
1 8
1 9
PC
2 0