Octagon 6000 Series, User Manual

Page: 83 / 233

6-18
EZ I/O 6000 Series user’s manual
xxxxxxxxB Data for port C
DX ffffh
Return registers: Carry flag cleared if successful
Carry flag set if error
AL
Error code
Comments: This function is used to write to the first 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 */
asm {
mov
ax,0ef01h
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 (1)
Function: efh
Subfunction: 02h
Purpose: To read from an EZ I/O port.
Calling registers: AH efh
AL
02h
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 first 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,0ef02h
mov dx,0ffffh
int 17h
mov aData,al