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void TC_select_host(int status)
{
regs.h.ah = 0x1C;
regs.h.al = (unsigned char)status;
regs.h.bh = 0;
int86(0x21,&regs,&regs);
}
1C Set host port protocol
Entry Parameters: AH = 1C
BH = 1
AL = 2 ; Multi-point (default)
3 ; None protocol
Returned Valued: None
void TC_protocol(int status)
{
regs.h.ah = 0x1C;
regs.h.al = (unsigned char)status;
regs.h.bh = 1;
int86(0x21,&regs,&regs);
}
1C Set serial port flow control
The system provides three handshaking mode for serial port: XON/XOFF,
CTR/RTS and none. The system default flow control for serial port is ?
ONE”. The CTS/RTS is only available while the RS-232 is designated to
serial port.
Entry Parameters: AH = 1C
BH = 2
AL = 0 ; None
1 ; XON/XOFF
2 ; CTS/RTS
Returned Value: None
??NOTE:
If you want to control the hand shaking flow of serial port, you must set the
flow control as “NONE”.
void TC_flow_ctrl(int status)
{
regs.h.ah = 0x1C;
regs.h.al = (unsigned char)status;
regs.h.bh = 2;
int86(0x21,&regs,&regs);