H8SSLASH2218 datasheet(589/750 Pages) RENESAS

Il numero della parte	H8S/2218

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

PDF	750 Pages

Scroll/Zoom	100%

Produttore elettronici	RENESAS [Renesas Technology Corp]

Homepage	http://www.renesas.com

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589 / 750 page

Section 15 A/D Converter

Rev.6.00 Jun. 03, 2008 Page 541 of 698

REJ09B0074-0600

15.4

Interface to Bus Master

ADDRA to ADDRD are 16-bit registers. As the data bus to the bus master is 8 bits wide, the bus

master accesses to the upper byte of the registers directly while to the lower byte of the registers

via the temporary register (TEMP).

Data in ADDR is read in the following way: When the upper-byte data is read, the upper-byte data

will be transferred to the CPU and the lower-byte data will be transferred to TEMP. Then, when

the lower-byte data is read, the lower-byte data will be transferred to the CPU.

When data in ADDR is read, the data should be read from the upper byte and lower byte in the

order. When only the upper-byte data is read, the data is guaranteed. However, when only the

lower-byte data is read, the data is not guaranteed.

Figure 15.2 shows data flow when accessing to ADDR.

TEMP

(H'40)

ADDRnL

(H'40)

ADDRnH

(H'AA)

TEMP

(H'40)

ADDRnL

(H'40)

ADDRnH

(H'AA)

Read the upper byte

Read the lower byte

(n = A to D)

Module data bus

Bus interface

Bus master

(H'40)

Bus master

(H'AA)

Figure 15.2 Access to ADDR (When Reading H'AA40)

H8S/2218 Scheda tecnica(PDF) 589 Page - Renesas Technology Corp