}

regs.h.ah = 0; regs.h.al = cc; int86(0x34,®s,®s);

}

05Set RTS signal of RS-232 port

Entry Parameters: AH = 5

AL = 2

DH = 0 ;set RTS to LOW

1 ;set RTS to HIGH (default)

Returned Values: None

void TC_232_RTS(int rts)

{

regs.h.ah = 5; regs.h.al = 2;

regs.h.dh = (unsigned char)rts; int86(0x34,®s,®s);

}

06Read CTS signal of RS-232 port

Entry Parameters: AH = 6

 

AL =

2

 

Returned Values:

DH =

0

;when CTS is LOW

 

 

1

;when CTS is HIGH

int TC_232_CTS()

{

regs.h.ah = 6; regs.h.al = 2; int86(0x34,®s,®s); return((int)regs.h.dh);

}

NOTE:

1)If the RS-232 port is controlled by use of INT 34H, and the port acts as the host port. You must set the protocol as ? ONE”.

RS-485 port serial I/O using INT 33H

01

Input data

 

 

Entry Parameters:

AH = 1

 

Returned Values:

1) if a character received

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Unitech MR350MKII Set RTS signal of RS-232 port, Read CTS signal of RS-232 port, RS-485 port serial I/O using INT 33H