Datasheet

Section 7 Data Transfer Controller [H8S/2138 Group]
Rev. 4.00 Jun 06, 2006 page 165 of 1004
REJ09B0301-0400
7.2.3 DTC Source Address Register (SAR)
23 22 21 20 19 43210
Bit
Initial value
Unde-
fined
Read/write
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
SAR is a 24-bit register that designates the source address of data to be transferred by the DTC.
For word-size transfer, specify an even source address.
7.2.4 DTC Destination Address Register (DAR)
23 22 21 20 19 43210
Bit
Initial value
Unde-
fined
Read/write
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
DAR is a 24-bit register that designates the destination address of data to be transferred by the
DTC. For word-size transfer, specify an even destination address.
7.2.5 DTC Transfer Count Register A (CRA)
15 14 13 12 11109876543210
CRAH CRAL
Bit
Initial value
Unde-
fined
Read/Write
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
Unde-
fined
CRA is a 16-bit register that designates the number of times data is to be transferred by the DTC.
In normal mode, the entire CRA register functions as a 16-bit transfer counter (1 to 65,536). It is
decremented by 1 every time data is transferred, and transfer ends when the count reaches H'0000.
In repeat mode or block transfer mode, CRA is divided into two parts: the upper 8 bits (CRAH)
and the lower 8 bits (CRAL). CRAH holds the number of transfers while CRAL functions as an 8-
bit transfer counter (1 to 256). CRAL is decremented by 1 every time data is transferred, and the
contents of CRAH are transferred when the count reaches H'00. This operation is repeated.