M306N5FCTFP Renesas Electronics America, M306N5FCTFP Datasheet - Page 274

• Manufacturer Part Number: M306N5FCTFP
• Description: IC M16C MCU FLASH 100QFP
• Manufacturer: Renesas Electronics America
• Series: M16C™ M16C/6Nr

Specifications of M306N5FCTFP

• Core Processor: M16C/60
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: CAN, I²C, IEBus, SIO, UART/USART
• Peripherals: DMA, WDT
• Number Of I /o: 87
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: FLASH
• Ram Size: 5K x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 26x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

Figure 5.3.2 Stack status before and after an interrupt request is acknowledged
Chapter 5
Table 5.3.2 Relationship between Interrupts without Interrupt Priority Levels and IPL
Address
5.3.2 Changes of IPL When Interrupt Request Acknowledged
5.3.3 Saving Registers
Stack status before interrupt request is acknowledged
Interrupt sources without interrupt priority levels
Watchdog timer, NMI
Reset
Other
When an interrupt request is acknowledged, the interrupt priority level of the acknowledged interrupt is
set to the processor interrupt priority level (IPL).
If an interrupt request is acknowledged that does not have an interrupt priority level, the value shown in
Table 5.3.2 is set to the IPL.
In an interrupt sequence, only the contents of the flag register (FLG) and program counter (PC) are
saved to the stack area.
The order in which these contents are saved is as follows: First, the 4 high-order bits of the program
counter and 4 high-order bits and 8 low-order bits of the FLG register for a total of 16 bits are saved to
the stack area. Next, the 16 low-order bits of the program counter are saved. Figure 5.3.2 shows the
stack status before an interrupt request is acknowledged and the stack status after an interrupt request
is acknowledged.
If there are any other registers you want to be saved, save them in software at the beginning of the
interrupt routine. The PUSHM instruction allows you to save all registers except the stack pointer (SP)
by a single instruction.
m–4
m–3
m–2
m–1
m
m+1
MSB
Content of
previous stack
Content of
previous stack
Stack area
Interrupt
_______
LSB
[SP]
Stack pointer
value before
interrupt occurs
256
Address
Stack status after interrupt request is acknowledged
Value that is set to IPL
m–4
m–3
m–2
m–1
m
m+1
MSB
Not changed
Flag register
Content of
previous stack
Content of
previous stack
Program counter
Program counter
Flag register
(FLG
Stack area
7
0
(FLG
H
)
(PC
(PC
L
M
L
)
)
)
Program counter
(PC
5.3 Interrupt Sequence
H
)
LSB
[SP]
New stack
pointer value