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Is it OK to use interrupt request signal for on-chip peripheral to CPU?

Latest Updated:03/25/2009

Question:

When the interrupt request signal from on-chip peripheral module is used as a transfer request signal on the on-chip peripheral module of DMAC, is it possible to use this interrupt request signal as the interrupt signal to CPU after transferring DMAC?

Answer:

The interrupt request signal for on-chip peripheral module specified as activation source of DMAC cannot be used as the interrupt request signal to CPU because the signal is not inputted in the interrupt controller (INTC).

If you want this interrupt request signal to be used as the interrupt signal to CPU, please do either of following processing after transferring DMAC.

•By changing the setting for resource select bit (RSn) of DMAC channel control register (CHCR), it doesn’t select as the activation source of DMAC.

•By setting DMAC master enable bit (DME) of DMA operation register (DMAOR) to “0”, set DMAC to the operation disabled. 

Moreover, DMAC has the function that generates the interrupt signals after transferring is completed for the specified time.

It can be activated by setting the interrupt enable bit (IEn) of DMA channel control register (CHCR) to “1”.

Suitable Products
SH7144, SH7145
SH7065
SH7058
SH7055
SH7050, SH7051
SH7052, SH7053, SH7054
SH7040, SH7041, SH7042, SH7043, SH7044, SH7045
SH7014, SH7016, SH7017