DS72030W200FPV Renesas Electronics America, DS72030W200FPV Datasheet - Page 462

• Manufacturer Part Number: DS72030W200FPV
• Description: MPU, 32BIT, SH7203, ROMLESS, 240QFP
• Manufacturer: Renesas Electronics America
• Series: SH7200r

Specifications of DS72030W200FPV

• Core Size: 32bit
• Program Memory Size: 32KB
• Cpu Speed: 200MHz
• Digital Ic Case Style: QFP
• No. Of Pins: 240
• Supply Voltage Range: 1.1V To 1.3V
• Operating Temperature Range: -20°C To +85°C
• Svhc: No SVHC
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Section 10 Direct Memory Access Controller (DMAC)
Figure 10.4 shows how the priority order changes when channel 0 and channel 3 transfers are
requested simultaneously and a channel 1 transfer is requested during the channel 0 transfer. The
DMAC operates as follows:
1. Transfer requests are generated simultaneously to channels 0 and 3.
2. Channel 0 has a higher priority, so the channel 0 transfer begins first (channel 3 waits for
3. A channel 1 transfer request occurs during the channel 0 transfer (channels 1 and 3 are both
4. When the channel 0 transfer ends, channel 0 is given the lowest priority among the round-robin
5. At this point, channel 1 has a higher priority than channel 3, so the channel 1 transfer begins
6. When the channel 1 transfer ends, channel 1 is given the lowest priority among the round-robin
7. The channel 3 transfer begins.
8. When the channel 3 transfer ends, channels 3 and 2 are lowered in priority so that channel 3 is
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REJ09B0313-0300
transfer).
waiting)
channels.
(channel 3 waits for transfer).
channels.
given the lowest priority among the round-robin channels.
Transfer request
(1) Channels 0 and 3
(3) Channel 1
Figure 10.4 Changes in Channel Priority in Round-Robin Mode
Waiting channel(s)
1, 3
3
3
None
(2) Channel 0 transfer start
(4) Channel 0 transfer ends
(5) Channel 1 transfer starts
(6) Channel 1 transfer ends
(7) Channel 3 transfer starts
(8) Channel 3 transfer ends
DMAC operation
Priority order
changes
Priority order
changes
Priority order
changes
Channel priority
0 > 1 > 2 > 3 > 4 > 5 > 6 > 7
1 > 2 > 3 > 0 > 4 > 5 > 6 > 7
2 > 3 > 0 > 1 > 4 > 5 > 6 > 7
0 > 1 > 2 > 3 > 4 > 5 > 6 > 7