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Section 10 Interrupt Controller (INTC)
Rev. 4.00 Sep. 14, 2005 Page 233 of 982
REJ09B0023-0400
10.4 Interrupt
Sources
There are four types of interrupt sources: NMI, H-UDI, IRQ, and on-chip peripheral modules.
Each interrupt has a priority level (0 to 16), with 1 the lowest and 16 the highest. Priority level 0
masks an interrupt, so the interrupt request is ignored.
10.4.1 NMI
Interrupt
The NMI interrupt has the highest priority level of 16. When the BL bit in the status register (SR)
is 0, NMI interrupts are accepted. NMI interrupts are edge-detected. In sleep or standby mode, the
interrupt is accepted regardless of the BL setting. The NMI edge select bit (NMIE) in the interrupt
control register 0 (ICR0) is used to select either rising or falling edge detection.
When using edge-input detection for NMI interrupts, a pulse width of at least two P
φ
cycles
(peripheral clock) is necessary. NMI interrupt exception handling does not affect the interrupt
mask level bits (I3 to I0) in the status register (SR).
It is possible to wake the chip up from sleep mode or standby mode with an NMI interrupt.
10.4.2 H-UDI
Interrupt
The H-UDI interrupt is accepted between one instruction and another when the H-UDI interrupt
command (section 15.4.5, H-UDI Interrupt.) is entered, the SR interrupt mask bit is set to the
value smaller than 15, and the BL bit in SR is set to 0.
The H-UDI interrupt allows the PC to be saved to the SPC immediately after accepting the
interrupt instruction. The SR at the time of the interrupt acceptation is saved to the SSR. The
INTEVT2 is set to H'5E0. The BL and RB bits in SR are set to 1 and branched to VBR + H'0600.
10.4.3 IRQ
Interrupts
IRQ interrupts are input by level or edge from pins
IRQ7
to
IRQ0
. The priority can be set by
interrupt priority registers C and D (IPRC and IPRD) in a range from 0 to 15.
When using edge-sensing for IRQ interrupts, clear the interrupt source by having software read 1
from the corresponding bit in IRR0, then write 0 to the bit.
When ICR1 and ICR3 are overwritten, IRQ interrupts may be mistakenly detected, depending on
the
IRQ
pin level. To prevent this, overwrite the register while interrupts are masked, then release
the mask after clearing the illegal interrupt by writing 0 to interrupt request register 0 (IRR0).
Summary of Contents for HD6417641
Page 2: ...Rev 4 00 Sep 14 2005 Page ii of l...
Page 7: ...Rev 4 00 Sep 14 2005 Page vii of l...
Page 11: ...Rev 4 00 Sep 14 2005 Page xi of l USB Universal serial bus WDT Watch dog timer...
Page 12: ...Rev 4 00 Sep 14 2005 Page xii of l...
Page 28: ...Rev 4 00 Sep 14 2005 Page xxviii of l...
Page 204: ...Section 4 Clock Pulse Generator CPG Rev 4 00 Sep 14 2005 Page 154 of 982 REJ09B0023 0400...
Page 212: ...Section 5 Watchdog Timer WDT Rev 4 00 Sep 14 2005 Page 162 of 982 REJ09B0023 0400...
Page 228: ...Section 6 Power Down Modes Rev 4 00 Sep 14 2005 Page 178 of 982 REJ09B0023 0400...
Page 246: ...Section 8 X Y Memory Rev 4 00 Sep 14 2005 Page 196 of 982 REJ09B0023 0400...
Page 318: ...Section 11 User Break Controller UBC Rev 4 00 Sep 14 2005 Page 268 of 982 REJ09B0023 0400...
Page 454: ...Section 12 Bus State Controller BSC Rev 4 00 Sep 14 2005 Page 404 of 982 REJ09B0023 0400...
Page 504: ...Section 14 U Memory Rev 4 00 Sep 14 2005 Page 454 of 982 REJ09B0023 0400...
Page 566: ...Section 17 Compare Match Timer CMT Rev 4 00 Sep 14 2005 Page 516 of 982 REJ09B0023 0400...
Page 868: ...Section 21 A D Converter Rev 4 00 Sep 14 2005 Page 818 of 982 REJ09B0023 0400...
Page 914: ...Section 23 I O Ports Rev 4 00 Sep 14 2005 Page 864 of 982 REJ09B0023 0400...
Page 956: ...Section 24 List of Registers Rev 4 00 Sep 14 2005 Page 906 of 982 REJ09B0023 0400...
Page 1016: ...Section 25 Electrical Characteristics Rev 4 00 Sep 14 2005 Page 966 of 982 REJ09B0023 0400...
Page 1024: ...Appendix Rev 4 00 Sep 14 2005 Page 974 of 982 REJ09B0023 0400...
Page 1032: ...Rev 4 00 Sep 14 2005 Page 982 of 982 REJ09B0023 0400 X X Y data addressing 52 X Y memory 193...
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