请帮忙将这段c++ builder code 翻译成 delphi code
//函数申明
int PlpOpen(unsigned int baudrate);
void PlpClose();
int PlpRead(unsigned char *portname, unsigned char *addr, unsigned char *buf, int *readlen);
int PlpRead(unsigned char *portname, unsigned char *addr, unsigned char *buf, int readlen);
int PlpReadAppoint(unsigned char *portname, unsigned char addr, unsigned char *buf, int n);
int PlpWrite(unsigned char *portname, unsigned char addr, unsigned char *buf, int n);
//函数调用
void __fastcall TForm1::Timer1Timer(TObject *Sender)
{
int ret1, ret2, readlen;
unsigned char addr, portname[10];
unsigned char rbuf[260];
Timer1->Enabled = false;
Timer1->Interval = 50;
readnext:
ret1 = PlpRead(portname, &addr, rbuf, &readlen);
if( readlen == 0 || ret1 < 0 )
{
Timer1->Enabled = true;
return;
}
do{
ret2 = PlpWrite(portname,addr,rbuf,readlen);
}while( ret2 < readlen);
if( ret1 > 0 ) goto readnext;
Timer1->Enabled = true;
}
//---------------------------------------------------------------------------