SH7059 Datasheet, PDF (861/1042 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

Main processing
25. ROM (SH7059)
Contention between
SCO and interrupt
SCO download
processing
Interrupt processing,
e.g. NMI
Figure 25.22 Contention between Interrupts (e.g. NMI)
• The NMI, UBC, or H-UDI interrupt processing is started. Processing proceeds up to the point where SR and PC
are saved, the vector is fetched, and the start instruction of the interrupt processing routine is fetched.
• At this point, the SCO download request with a higher priority occurs. The SCO download processing is
started.
• After the download processing has ended, the interrupt processing routine (e.g. NMI) that was in the middle of
execution resumes from the point of fetching the start instruction of the interrupt processing routine.
• The interrupt processing routine is ended, and execution returns to the main processing.
⎯ IRQ and on-chip peripheral module interrupt requests
Operation for when these interrupts conflict with the SCO download request is described below.
Main processing
Contention between
SCO and interrupt
SCO download
processing
Interrupt processing,
e.g. IRQ
Figure 25.23 Contention between Interrupts (e.g. IRQ)
• An IRQ interrupt or interrupt from an on-chip peripheral module is replaced with the SCO download request
and download is executed.
• If the IRQ or on-chip peripheral module interrupt is still being requested when the download processing has
ended, the interrupt processing is executed. If these interrupt requests have been canceled, execution returns to
the main processing.
• An interrupt request is canceled when the IRQ signal, for which low-level detection is set, has been driven high
before download ends. Also refer to the description below (3. Interrupt requests generated during download).
Rev.3.00 Mar. 12, 2008 Page 771 of 948
REJ09B0177-0300