•
Block transfer mode
ETCRA
ETCRB
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.
Bit
Initial value
Read/Write
7
R/W
6
R/W
5
R/W
4
R/W
3
R/W
0
R/W
2
R/W
1
R/W
Undetermined
Block size counter
ETCRAH
Bit
Initial value
Read/Write
7
R/W
6
R/W
5
R/W
4
R/W
3
R/W
0
R/W
2
R/W
1
R/W
Undetermined
Initial block size
ETCRAL
Bit
Initial value
Read/Write
14
R/W
12
R/W
10
R/W
8
R/W
6
R/W
0
R/W
4
R/W
2
R/W
Block transfer counter
Undetermined
15
R/W
13
R/W
11
R/W
9
R/W
7
R/W
1
R/W
5
R/W
3
R/W
198
www.DataSheet4U.com