HD6417751 Datasheet, PDF (505/1105 Pages) Renesas Technology Corp – SuperH RISC engine

• Channel 7 (SH7751R only): Single or dual address mode. External requests are
accepted.
In DDT mode, data transfer is carried out by the SH7751 using the '%5(4, %$9/, 75,
7'$&K, ID [1:0], and D[31:0] signals to perform handshaking between the external
device and the DMAC, and data transfer is carried out by the SH7751R using the '%5(4,
%$9/, 75, 7'$&., ID [2:0], and D[31:0] signals to perform handshaking between the
external device and the DMAC.
• Request-queue clear for each channel (SH7751R only)
Request queues can be cleared on a channel-by-channel basis in either of the following two
ways.
 Clearing a request queue by DTR format
The request queues of the relevant channel are cleared when it receives DTR.SZ = 110,
DTR.ID = 00, DTR.MD = 11, and DTR.COUNT [7:4]* = [1–8].
 Using software to clear the request queue
The request queues of the relevant channel are cleared by writing a 1 to the CHCRn.QCL
bit (request-queue clear bit) of each channel.
Note: * DTR.COUNT [7:4] (DTR [23:20]): Sets the port as not used.
Rev. 3.0, 04/02, page 465 of 1064