
III PERIPHERAL MODULES 1 (SYSTEM): INTERRUPT CONTROLLER (ITC)
S1C33E07 TECHNICAL MANUAL
EPSON
III-2-13
III
ITC
III.2.6 HSDMA Invocation
Some causes of interrupt can invoke high-speed DMAs (HSDMA).
HSDMA trigger set-up register
The DMA block contains four channel of HSDMA circuit. Each channel allows selection of a cause of interrupt
as the trigger. HSDxS[3:0] (0x300298–0x300299) is used for this selection.
HSD0S[3:0]: Ch.0 Trigger Set-up Bits in the HSDMA Ch.0–1 Trigger Set-up Register (D[3:0]/0x300298)
HSD1S[3:0]: Ch.1 Trigger Set-up Bits in the HSDMA Ch.0–1 Trigger Set-up Register (D[7:4]/0x300298)
HSD2S[3:0]: Ch.2 Trigger Set-up Bits in the HSDMA Ch.2–3 Trigger Set-up Register (D[3:0]/0x300299)
HSD3S[3:0]: Ch.3 Trigger Set-up Bits in the HSDMA Ch.2–3 Trigger Set-up Register (D[7:4]/0x300299)
Table III.2.6.1 shows the setting value and the corresponding trigger source.
Table III.2.6.1 HSDMA Trigger Source
Value
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
Ch.0 trigger source
Software trigger
#DMAREQ0 input (falling edge)
#DMAREQ0 input (rising edge)
Port 0 input
Port 4 input
(reserved)
16-bit timer 0 compare B
16-bit timer 0 compare A
16-bit timer 4 compare B
I2S left
Serial I/F Ch.0 Rx buffer full
Serial I/F Ch.0 Tx buffer empty
A/D conversion completion
Port 8 input (SPI interrupt)
Port 12 input
Ch.1 trigger source
Software trigger
#DMAREQ1 input (falling edge)
#DMAREQ1 input (rising edge)
Port 1 input
Port 5 input
(reserved)
16-bit timer 1 compare B
16-bit timer 1 compare A
16-bit timer 5 compare B
I2S right
Serial I/F Ch.1 Rx buffer full
Serial I/F Ch.1 Tx buffer empty
A/D conversion completion
Port 9 input (USB PDREQ)
Port 13 input
Ch.2 trigger source
Software trigger
#DMAREQ2 input (falling edge)
#DMAREQ2 input (rising edge)
Port 2 input
Port 6 input
(reserved)
16-bit timer 2 compare B
16-bit timer 2 compare A
(reserved)
SPI transmit DMA request
Serial I/F Ch.2 Rx buffer full
Serial I/F Ch.2 Tx buffer empty
A/D conversion completion
Port 10 input (USB interrupt)
Port 14 input
Ch.3 trigger source
Software trigger
#DMAREQ3 input (falling edge)
#DMAREQ3 input (rising edge)
Port 3 input
Port 7 input
(reserved)
16-bit timer 3 compare B
16-bit timer 3 compare A
(reserved)
SPI receive DMA request
(reserved)
A/D conversion completion
Port 11 input (DCSIO interrupt)
Port 15 input
Invoking HSDMA
By selecting a cause of interrupt with the HSDMA trigger set-up register, the HSDMA channel is invoked
when the selected cause of interrupt occurs. The interrupt control bits (cause-of-interrupt flag, interrupt enable
register, IDMA request register, interrupt priority register) do not affect this invocation.
The interrupt request to the CPU by the cause of interrupt that invokes HSDMA is output two clocks (MCLK)
after the HSDMA request, so the DMA transfer and interrupt handling are performed concurrently when the
CPU runs with the instructions in the cache. However, when the interrupt handler contains an instruction that
accesses a peripheral circuit, the execution of the instruction is pending until the DMA transfer is completed
since the bus is used by the HSDMA.
Before HSDMA can be invoked by the occurrence of a cause of interrupt, it is necessary that DMA be enabled
on the HSDMA side by setting the control register for HSDMA transfer.
For details about HSDMA, refer to Section II.1, “High-Speed DMA (HSDMA).”