Execute Transfer Count Register (Etcr) - Renesas H8S/2633 Series Hardware Manual

8.3.3

Execute Transfer Count Register (ETCR)

ETCR is a 16-bit readable/writable register that specifies the number of transfers. The function of
this register is different in normal mode and in block transfer mode.
ETCR is not initialized by a reset or in standby mode.
(1) Normal Mode
ETCRA
Transfer Counter
Bit : 15
ETCR :
Initial value : *
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 R/W
In normal mode, ETCRA functions as a 16-bit transfer counter. ETCRA is decremented by 1 each
time a transfer is performed, and transfer ends when the count reaches H'0000. ETCRB is not used
at this time.
ETCRB
ETCRB is not used in normal mode.
(2) Block Transfer Mode
ETCRA
Holds block size
Bit : 15
ETCRAH :
Initial value :
*
R/W : R/W
Block size counter
Bit : 7
ETCRAL :
Initial value :
*
R/W : R/W
260
14 13 12 11 10
* * * *
14 13
* *
R/W R/W
6 5
* *
R/W R/W
9 8 7 6
* * * * *
12 11
* *
R/W R/W
4 3
* *
R/W R/W
5 4 3 2 1
* * * * *
*: Undefined
10 9
* *
R/W R/W
2 1
* *
R/W R/W
*: Undefined
0
*
8
*
R/W
0
*
R/W