HD64F3048F16 Datasheet, PDF (241/903 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 8 DMA Controller
Block transfer mode
ETCRA:
Bit
7
6
5
4
3
2
1
0
Initial value
Read/Write
Bit
Undetermined
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
ETCRAH
Block size counter
7
6
5
4
3
2
1
0
Initial value
Read/Write
Undetermined
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
ETCRAL
ETCRB:
Bit
Initial block size
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Initial value
Read/Write
Undetermined
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W
Block transfer counter
In block transfer mode, ETCRAH functions as an 8-bit block size counter. ETCRAL holds the
initial block size. ETCRAH is decremented by 1 each time one byte or word is transferred. When
the count reaches H'00, ETCRAH is reloaded from ETCRAL. Blocks consisting of an arbitrary
number of bytes or words can be transferred repeatedly by setting the same initial block size value
in ETCRAH and ETCRAL.
In block transfer mode ETCRB functions as a 16-bit block transfer counter. ETCRB is
decremented by 1 each time one block is transferred. The transfer ends when the count reaches
H'0000.
The ETCRs are not initialized by a reset or in standby mode.
Rev. 3.00 Sep 27, 2006 page 213 of 872
REJ09B0325-0300