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SH7263/SH7203 Group
Data Transfer to On-chip Peripheral Modules with DMAC
REJ06B0734-0100/Rev.1.00 April 2008 Page 3 of 17
2. Description of Sample Application
In this sample application, the DMAC and on-chip peripheral module requests are used to transfer data from external
memory to the SCIF.
2.1 Operational Overview of Modules Used
When a DMA transfer request is made, the DMAC starts to transfer data in accordance with the priority order of
channels, and continues the transfer operation until the transfer end condition is met. Transfer requests for the DMAC
are of three kinds: auto requests, external requests, and on-chip peripheral module requests. The bus mode is selectable
as burst mode or cycle-stealing mode.
An overview of the DMAC is given in table 1. Also, a block diagram of the DMAC is shown in figure 1.
Table 1 Overview of DMAC
Item Description
Number of channels
8 (CH0 to CH7)
Only 4 (CH0 to CH3) can receive external requests.
Address space 4 Gbytes
Length of transfer data Byte, word (2 bytes), longword (4 bytes), and 16 bytes (longword × 4)
Maximum transfer
count
16,777,216 (24 bits) transfers
Address mode Single address mode and dual address mode
Transfer request Auto request, external request, and on-chip peripheral module request
• SH7203/SH7263
(SCIF: 8 sources, I
2
C3: 8 sources, ADC: 1 source, MTU2: 5 sources, CMT: 2
sources, USB: 2 sources, FLCTL: 2 sources, RCAN-TL1: 2 sources, SSI: 4
sources, SSU: 4 sources)
• SH7263
(SRC: 2 sources, ROM-DEC: 1 source, SDHI: 2 sources)
Bus mode Cycle-stealing mode and burst mode
Priority level Channel priority fixed mode and round-robin mode
Interrupt request
An interrupt request to the CPU is made when half or all of a transfer process is
completed.
External request
detection
DREQ input low/high level detection, rising/falling edge detection
Transfer request
acknowledge
signal/transfer end
signal
Active levels for DACK and TEND can be set independently
Note: For details on the DMAC, refer to the section on the direct memory access controller in the
SH7263/SH7203 Group Hardware Manual.