Octagon PC-510, User Manual

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11-11
PC-510 user’s manual EZ I/O
mov ax,0ef04h
mov di,00ffh /*port A: no change */
mov bx,8000h /*port B: bit 7=0, other bits unchanged*/
mov cx,0202h /*port C: bit 1=1, other bits unchanged*
mov dx,0ffffh
int 17h
}
Read EZ I/O 2
Function: efh
Subfunction: 05h
Purpose: To read from an EZ I/O port.
Calling registers:
AH efh
AL 05h
xxxxxxxx Data for port C
DX ffffh
Return registers: Carry flag cleared if successful
AL Port A data
AH Port B data
BL Port C data
Carry flag set if error
AL Error code
Comments: This function is used to read from the second EZ I/O
(i.e.,the EZ I/O that has the lower I/O address when
two EZ I/O chips are present on a board).
Programming Example:
/* Inline assembly code for Borland C++ 3.1 */
unsigned char aData, bData, cData;
asm {
mov ax,0ef05h
mov dx,0ffffh
int 17h
mov aData,al
mov bData,ah
mov cData,bl
}
≡
Opto-module rack interface
You can interface digital I/O lines to an 8-, 16-, or 24-position opto-module
rack. One end of the CMA-26 cable plugs into the EZ I/O connector and the
other plugs into an MPB-8, MPB-16, or an MPB-24 opto rack. Refer to the
MPB opto racks
data sheet for more information.