HD6473032F16 Datasheet, PDF (224/847 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

Section 8 DMA Controller
8.2.3 Execute Transfer Count Registers (ETCR)
An execute transfer count register (ETCR) is a 16-bit readable/writable register that specifies the
number of transfers to be executed. These registers function in one way in I/O mode and idle
mode, and another way in repeat mode.
• I/O mode and idle mode
Bit
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
Transfer counter
In I/O mode and idle mode, ETCR functions as a 16-bit counter. The count is decremented by
1 each time one transfer is executed. The transfer ends when the count reaches H'0000.
• Repeat mode
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
ETCRH
Transfer counter
7
6
5
4
3
2
1
0
Initial value
Undetermined
Read/Write
R/W
R/W R/W R/W R/W R/W R/W R/W
ETCRL
Initial count
Rev. 3.00 Mar 21, 2006 page 194 of 814
REJ09B0302-0300