Moxa Technologies NE-4100 - Manual (Page 84)

NE-4100 Series User’s Manual DIO Commands
C-4
4. Writing Multiple DIOs
Parameters:
Command code: 6(hex)
Version: 2(hex)
Command status: doesn’t matter
Length of data: (end-start+1)*2 + 2
data[0]: Number of the DIO you wish to access first.
data[1]: The last number of the DIO you wish to access
data[2]: mode of start DIO
data[3]: status of start DIO
data[4]:
mode of (start+1) DIO
data[5]: status of (start+1) DIO
….
data[(end-start)*2+2]: mode of end DIO
data[(end-start)*2+3]: status of end DIO
Return:
Command Status: Check the Command Status code on the previous page.
Length of data : (end-start+1)*2
data[0]: mode of start DIO
data[1]: status of start DIO
data[2]:
mode of (start+1) DIO
data[3]: status of (start+1) DIO
….
data[(end-start)*2]: mode of end DIO
data[(end-start)*2+1]: status of end DIO
C code example:
void WriteMultipleDIO(int start, int end, int* mode, int* status)
{
DIOPacketStruct packet;
packet.header.command = 6; // Write Multiple DIO Command Codes
packet.header.version = 2; // DIO protocol version
packet.header.length = (end-start+1)*2+2; // data length
packet.data[0] = start;
// start DIO number
packet.data[1] = end; // end DIO number
int i, len;
for ( i=0; i<(end-start+1);i++ ) {
packet.data[i+2] = mode[i];
packet.data[i+3] = status[i];
}
send(SocketFd, )(char*)&packet,( end-start+1)*2+2+sizeof(DIOHeaderStruct), 0); //Send TCP
packet
//Process the returned data here
}
Note: A utility that can be used to test the DIO access commands can be found on the CD-ROM.