DF3052BX25V Renesas Electronics America, DF3052BX25V Datasheet - Page 136

• Manufacturer Part Number: DF3052BX25V
• Description: MCU 5V 512K 100-TQFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8/300Hr

Specifications of DF3052BX25V

• Core Processor: H8/300H
• Core Size: 16-Bit
• Speed: 25MHz
• Connectivity: SCI, SmartCard
• Peripherals: DMA, POR, PWM, WDT
• Number Of I /o: 70
• Program Memory Size: 512KB (512K x 8)
• Program Memory Type: FLASH
• Ram Size: 8K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 100-TQFP, 100-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

Section 5 Interrupt Controller
Occurrence Conditions
1. If an ISR register read is executed to clear the IRQaF flag while IRQaF = 1, and then the
2. If there is contention between IRQaF flag clearing and IRQbF generation (IRQaF flag setting)
If above setting conditions 1 to 3 and occurrence conditions 1 and 2 are all fulfilled, IRQbF will be
cleared erroneously when the ISR write in occurrence condition 2 is executed, and so interrupt
exception handling will not be carried out.
However, the IRQbF flag will not be cleared erroneously if 0 is written to it at least once between
occurrence conditions 1 and 2.
Either of the following methods can be used to prevent this problem.
Rev. 3.00 Mar 21, 2006 page 106 of 814
REJ09B0302-0300
IRQaF
IRQbF
IRQbF flag is cleared by the initiation of interrupt exception handling.
(when IRQbF = 0 at the time of the ISR read to clear the IRQaF flag, but IRQbF is set to 1
before the write to ISR).
Solution 1
When IRQaF flag clears, do not use the bit computation command, read the ISR in bytes.
When IRQaF only is 0 write all other bits as 1 in bytes.
For example, if a = 0
Figure 5.9 IRQnF Flag when Interrupt Processing Is Not Conducted
Occurrence condition 1
Read
Read
1
1
Write
Write
0
1
Execution
IRQb
Occurrence condition 2
Clear in error
Read
Read
1
0
Write
Write
0
0