H8SSLASH2214 datasheet(253/936 Pages) RENESAS

Il numero della parte	H8S/2214

Spiegazioni elettronici	16-Bit Single-Chip Microcomputer H8S Family/H8S/2200 Series

PDF	936 Pages

Scroll/Zoom	100%

Produttore elettronici	RENESAS [Renesas Technology Corp]

Homepage	http://www.renesas.com

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253 / 936 page

Section 7 DMA Controller

Rev.4.00 Sep. 18, 2008 Page 193 of 872

REJ09B0189-0400

(2) Block Transfer Mode

ETCRA

Holds block size

Bit

ETCRAH

Initial value :

R/W

Block size counter

Bit

ETCRAL

Initial value :

R/W

*: Undefined

ETCRB

Block Transfer Counter

Bit

ETCRB

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 block transfer mode, ETCRAL functions as an 8-bit block size counter and ETCRAH holds the

block size. ETCRAL is decremented each time a 1-byte or 1-word transfer is performed, and when

the count reaches H'00, ETCRAL is loaded with the value in ETCRAH. So by setting the block

size in ETCRAH and ETCRAL, it is possible to repeatedly transfer blocks consisting of any

desired number of bytes or words.

ETCRB functions in block transfer mode, as a 16-bit block transfer counter. ETCRB is

decremented by 1 each time a block is transferred, and transfer ends when the count reaches

H'0000.

H8S/2214 Scheda tecnica(PDF) 253 Page - Renesas Technology Corp