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#include "busdevice.h"
#include "pcserialport.h"
#include <string.h>
#define BD_NONE 0
#define BD_RS 1
#define BD_FTDI 2
//how much bytes available in transmit buffer
#define TANSMIT_BUFFER_LENGTH 128
unsigned long SMBusBaudrate=SM_BAUDRATE; //the next opened port (with smOpenBus) will be opened with the PBS defined here (default 460800 BPS)
typedef struct _SMBusDevice
{
//common
smint8 bdType;//bus device type (such as rs232 or ftdi lib or mcu UART etc). 1=rs232 lib
smbool opened;
SM_STATUS cumulativeSmStatus;
//used for rs232 lib only
int comPort;
smuint8 txBuffer[TANSMIT_BUFFER_LENGTH];
smint32 txBufferUsed;//how many bytes in buffer currently
//used for FTDI lib only
} SMBusDevice;
//init on first open
smbool bdInitialized=smfalse;
SMBusDevice BusDevice[SM_MAX_BUSES];
//init device struct table
void smBDinit()
{
int i;
for(i=0;i<SM_MAX_BUSES;i++)
{
BusDevice[i].bdType=BD_NONE;
BusDevice[i].opened=smfalse;
BusDevice[i].txBufferUsed=0;
}
bdInitialized=smtrue;
}
//ie "COM1" "VSD2USB"
//return -1 if fails, otherwise handle number
smbusdevicehandle smBDOpen( const char *devicename )
{
int handle;
//true on first call
if(bdInitialized==smfalse)
smBDinit();
//find free handle
for(handle=0;handle<SM_MAX_BUSES;handle++)
{
if(BusDevice[handle].opened==smfalse) break;//choose this
}
//all handles in use
if(handle>=SM_MAX_BUSES) return -1;
if(strncmp(devicename,"COM",3) == 0 || strncmp(devicename,"/dev/tty",8) == 0) //use rs232 lib
{
BusDevice[handle].comPort=serialPortOpen( devicename, SMBusBaudrate );
if( BusDevice[handle].comPort == -1 )
{
return -1; //failed to open
}
BusDevice[handle].bdType=BD_RS;
BusDevice[handle].txBufferUsed=0;
}
else//no other bus types supproted yet
{
return -1;
}
//success
BusDevice[handle].cumulativeSmStatus=0;
BusDevice[handle].opened=smtrue;
return handle;
}
smbool smIsBDHandleOpen( const smbusdevicehandle handle )
{
if(handle<0) return smfalse;
if(handle>=SM_MAX_BUSES) return smfalse;
return BusDevice[handle].opened;
}
//return true if ok
smbool smBDClose( const smbusdevicehandle handle )
{
//check if handle valid & open
if( smIsBDHandleOpen(handle)==smfalse ) return smfalse;
if( BusDevice[handle].bdType==BD_RS )
{
serialPortClose( BusDevice[handle].comPort );
BusDevice[handle].opened=smfalse;
return smtrue;
}
return smfalse;
}
//write one byte to buffer and send later with smBDTransmit()
//returns true on success
smbool smBDWrite(const smbusdevicehandle handle, const smuint8 byte )
{
//check if handle valid & open
if( smIsBDHandleOpen(handle)==smfalse ) return smfalse;
if( BusDevice[handle].bdType==BD_RS )
{
if(BusDevice[handle].txBufferUsed<TANSMIT_BUFFER_LENGTH)
{
//append to buffer
BusDevice[handle].txBuffer[BusDevice[handle].txBufferUsed]=byte;
BusDevice[handle].txBufferUsed++;
return smtrue;
}
else
return smfalse;
}
return smfalse;
}
smbool smBDTransmit(const smbusdevicehandle handle)
{
//check if handle valid & open
if( smIsBDHandleOpen(handle)==smfalse ) return smfalse;
if( BusDevice[handle].bdType==BD_RS )
{
if(serialPortWriteBuffer(BusDevice[handle].comPort,BusDevice[handle].txBuffer, BusDevice[handle].txBufferUsed)==BusDevice[handle].txBufferUsed)
{
BusDevice[handle].txBufferUsed=0;
return smtrue;
}
else
{
BusDevice[handle].txBufferUsed=0;
return smfalse;
}
}
return smfalse;
}
//read one byte from bus. if byte not immediately available, block return up to SM_READ_TIMEOUT millisecs to wait data
//returns true if byte read sucessfully
smbool smBDRead( const smbusdevicehandle handle, smuint8 *byte )
{
//check if handle valid & open
if( smIsBDHandleOpen(handle)==smfalse ) return smfalse;
if( BusDevice[handle].bdType==BD_RS )
{
int n;
n=serialPortRead(BusDevice[handle].comPort, byte, 1);
if( n!=1 ) return smfalse;
else return smtrue;
}
return smfalse;
}
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