ICP DAS USA I-7188XB Series, User Manual

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4.12 Using the I/O Expansion Bus
As there are many serial interface devices available today, the I/O
expansion bus includes both serial and parallel interfaces. The parallel
interface is very similar to an ISA bus, so the old ISA bus design can be
migrated to the I/O expansion bus with a minimum amount of alteration.
The I/O pins of the serial bus are programmable and can be
programmed as either D/I or D/O.
The features of these serial devices are as follows:
Smaller size compared to parallel devices
Lower cost compared to parallel devices
Easier to design for isolated applications
The serial interface of the I/O expansion bus makes connecting to these
serial devices very easy.
4.12.1 Definition of an I/O Expansion Bus
The I/O expansion bus of the I-7188XB(D) module can be divided into 3
groups as follows:
1. Power supply and reset signals: VCC, GND, RESET and /RESET
2. Parallel Bus:
System clock: CLOCKA
Asynchronous ready control: ARDY
Address bus: A0 ~ A7
Data bus: D0 ~ D7
Interrupt control: INT0, INT1 and INT4
Chip select and read/write strobe: /CS, /WR and /RD
3. Serial Bus: TO_0, TO_1, TI_0, TI_1, SCLK, DIO9, DIO4 and DIO14
I-7188XB Series User’s Manual(Ver.1.0, Apr/2007, 7MH-020-10 ) ---
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