[51] Whats the meaning of this 2 code in 8051?

[HHM]

Hi,
I am new programmer in micro scale and I wanna work on AVR Atmega32.
I have code for 8051 micro(c and header file),and I need convert this code for use in AVR
I don't know whats the meaning of code :

unsigned char volatile xdata CH375_CMD_PORT _at_ 0xBDF1;
unsigned char volatile xdata CH375_DAT_PORT _at_ 0xBCF0;


I think its related to RX,TX of micro,because I wanna work with Rs232 to USB converter

thanks,
Regards,Hesam.H.Motiee

 

[FvM]

Review the hardware design to understand what's connected to external RAM space, apparently the said "CH375" interface. ATmega32 has no similar external data bus option, you have to refer e.g. to ATmega128 if you want to use it in your new design.

 

[HHM]

thanks for your attention