Can I put ?CO?xxx on XDATA space using LX51 user segments "?CO?xxx (X:0x200)" thx all
xdata is a RAM space isn't it. And Data that I put it in will be lost if burn hex file after into a micro, each time I cut off the electricity isnt it ?
Exactly. So, knowing that: do you still think that what you were asking about makes any sense whatsoever?
"xdata is a RAM space isn't it." Not necessarily. As far as the processor is concerned, XDATA is just memory that responds to MOVX opcodes; so, if you connect some ROM so that it responds to (ie, is accessed by) MOVX opcodes, you have ROM in XDATA space. If you want to do this, you need to look at the XCONST and XCROM options http://www.keil.com/support/man/docs/c51/c51_userclass.asp http://www.keil.com/support/man/docs/c51/c51_xcrom.htm I think this requires OMF2 and, therefore, LX51. See also: http://www.keil.com/forum/docs/thread4346.asp http://www.keil.com/forum/docs/thread2074.asp http://www.keil.com/forum/docs/thread3361.asp
"xdata is a RAM space isn't it." Not necessarily. As far as the processor is concerned, XDATA is just memory that responds to MOVX opcodes; so, if you connect some ROM so that it responds to (i.e. is accessed by) MOVX opcodes, you have ROM in XDATA space. expanding on this: the most frequent case I know of using "burned constants in XDATA" is in the cases where you use a negative OR to convert the '51 to vonNeuman memory. Erik