How to implement " char * strcopy(char * DestStr, char * SourceStr, uchar StartPos, uchar Count

"Keil C51 is very good." ===> "C51 is v" strcopy(DestStr, SourceStr, 6, 8) ? How to implement it ?
How to implement " char * strcopy(char * DestStr, char * SourceStr, uchar StartPos, uchar Count

"Keil C51 is very good." ===> "C51 is v" strcopy(DestStr, SourceStr, 6, 8) ? How to implement it ?
How can i read a char with 8051 from a char sent by Visual basic?

I'm doing a project with 2 pc embedded with bluetooth and a 8051 connected to one of the pc. i haf design a program codes using VB to send a char to the serial comm port to 8051 when the 2 pc disconnects...
How can i read a char with 8051 from a char sent by Visual basic?

I'm doing a project with 2 pc embedded with bluetooth and a 8051 connected to one of the pc. i haf design a program codes using VB to send a char to the serial comm port to 8051 when the 2 pc disconnects...
atoi doesn't work for all numbers

The function atoi (and sscanf, atof etc), all appear to have the same (unlikely) problem: they don't read the number 5. Yes, I realize that this seems very unlikely. I am using uVision version 4...