Renesas SH7641 - Manual (Page 668)

Section 18 Multi-Function Timer Pulse Unit (MTU)
Rev. 4.00 Sep. 14, 2005 Page 618 of 982
REJ09B0023-0400
Overflow Interrupt: An interrupt is requested if the TCIEV bit in TIER is set to 1 when the
TCFV flag in TSR is set to 1 by the occurrence of TCNT overflow on a channel. The interrupt
request is cleared by clearing the TCFV flag to 0. The MTU has five overflow interrupts, one for
each channel.
Underflow Interrupt: An interrupt is requested if the TCIEU bit in TIER is set to 1 when the
TCFU flag in TSR is set to 1 by the occurrence of TCNT underflow on a channel. The interrupt
request is cleared by clearing the TCFU flag to 0. The MTU has four underflow interrupts, one
each for channels 1 and 2.
18.5.2 DMA Activation
The DMA can be activated by a TGRA input capture/compare match interrupt in each channel.
If the TGFASEL bit in TIER is set to 1 when the TGFA flag in TSR is set to 1 due to the TGRA
input capture/compare match in each channel, the DMA transfer is requested to DMA. For details,
see section 13, Direct Memory Access Controller (DMAC).
A total of five MTU input capture/compare match interrupts can be used as DMA activation
sources for each channel
When using DMA, do not clear the flag by writing 0 after reading TGFA = 1. The flag can be
automatically cleared by DMA hardware. However, if a DMA address error occurs during a DMA
read cycle, the flag must be cleared using software by writing 0 after reading TGFA = 1.
18.5.3 A/D Converter Activation
The A/D converter can be activated by the TGRA input capture/compare match in each channel.
If the TTGE bit in TIER is set to 1 when the TGFA flag in TSR is set to 1 by the occurrence of a
TGRA input capture/compare match on a particular channel, a request to start A/D conversion is
sent to the A/D converter. If the MTU conversion start trigger has been selected on the A/D
converter at this time, A/D conversion starts.
In the MTU, a total of five TGRA input capture/compare match interrupts can be used as A/D
converter conversion start sources, one for each channel.