HD6417750SBP200 Renesas Electronics America, HD6417750SBP200 Datasheet - Page 655

• Manufacturer Part Number: HD6417750SBP200
• Description: IC SUPERH MPU ROMLESS 256BGA
• Manufacturer: Renesas Electronics America
• Series: SuperH® SH7750r

Specifications of HD6417750SBP200

• Core Processor: SH-4
• Core Size: 32-Bit
• Speed: 200MHz
• Connectivity: EBI/EMI, FIFO, SCI, SmartCard
• Peripherals: DMA, POR, WDT
• Number Of I /o: 28
• Program Memory Type: ROMless
• Ram Size: 24K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 2.07 V
• Oscillator Type: External
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 256-BGA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Program Memory Size: -
• Data Converters: -

Section 14 Direct Memory Access Controller (DMAC)
14.3.2
DMA Transfer Requests
DMA transfer requests are basically generated at either the data transfer source or destination, but
they can also be issued by external devices or on-chip peripheral modules that are neither the
source nor the destination.
Transfers can be requested in three modes: auto-request, external request, and on-chip peripheral
module request. The transfer request mode is selected by means of bits RS3–RS0 in DMA channel
control registers 0–3 (CHCR0–CHCR3).
Auto Request Mode: When there is no transfer request signal from an external source, as in a
memory-to-memory transfer or a transfer between memory and an on-chip peripheral module
unable to request a transfer, the auto-request mode allows the DMAC to automatically generate a
transfer request signal internally. When the DE bit in CHCR0–CHCR3 and the DME bit in the
DMA operation register (DMAOR) are set to 1, the transfer begins (so long as the TE bit in
CHCR0–CHCR3 and the NMIF and AE bits in DMAOR are all 0).
External Request Mode: In this mode a transfer is performed in response to a transfer request
signal (DREQ) from an external device. One of the modes shown in table 14.4 should be chosen
according to the application system. If DMA transfer is enabled (DE = 1, DME = 1, TE = 0, NMIF
= 0, AE = 0), transfer starts when DREQ is input. The DS bit in CHCR0/CHCR1 is used to select
either falling edge detection or low level detection for the DREQ signal (level detection when DS
= 0, edge detection when DS = 1).
DREQ is accepted after a power-on reset if TE = 0, NMIF = 0, and AE = 0, but transfer is not
executed if DMA transfer is not enabled (DE = 0 or DME = 0).
In this case, DMA transfer is started when enabled (by setting DE = 1 and DME = 1).
Rev.7.00 Oct. 10, 2008 Page 569 of 1074
REJ09B0366-0700