User`s manual

Serial Programming Tools
Intellio C218Turbo User's Manual 4-11
7. MHWFLOW
This function is used to enable/disable hardware flow control. The first open()
function of a port will set the hardware flow control bits on or off depending on the
[RTS/CTS Hardware Flow Control] configuration in mxadm. However, users
might want to control the DTR or RTS signal on their will, thus the RTS flow
control bit should be turned off (HWFLowControlOff) in order to take over the
control of DTR or RTS signal via function MTCRTS or MTCDTR. MTCRTS and
MTCDTR can be effective only after the RTS flow control bit of MHWFLOW is
turned off.
Syntax for SCO UNIX/XENIX
#define MHWFLOW 0x40e
#define HWFlowControlOff 0x00
#define CTSFlowControlBitOn 0x01
#define RTSFlowControlBitOn 0x02
#define HWFlowControlOn 0x03
ioctl(moxa_fd, MHWFLOW, CTSFlowControlBitOn);
ioctl(moxa_fd, MHWFLOW, RTSFlowControlBitOn);
ioctl(moxa_fd,MHWFLOW, CTSFlowControlBitOn | RTSFlowControlBitOn);
Syntax for UNIX SVR4
#include <sys/stropts.h>
#include <sys/sysmacros.h>
#define MHWFLOW 0x40e
#define HWFlowControlOff 0x00
#define CTSFlowControlBitOn 0x01
#define RTSFlowControlBitOn 0x02
#define HWFlowControlOn 0x03
struct strioctl ioc;
int setting;
setting = CTSFlowControlbitOn;
ioc.ic_cmd = MHWFLOW;
ioc.ic_timout = 0;
ioc.ic_len = sizeof(int);
ioc.ic_dp = (char *)&setting;
ioctl(moxa_fd, I_STR, &ioc);