Can we use large memory model in Evalation version of Keil for C51.
Thanks for giving links.
I wil study it first and understand. If i have doubt than i will ask you.
Thanks once again...
I want to interface device which communicate through serial communication with uC. I checked this device using serial port analyzer it is responding but when i am giving that commands using uC it is not responding. show your code
if i am accessing memory of that device then i have to use xdata variables so i have to use large memory model thats why i am asking can we use it. why? what does the memory of another device have to do with the memory you use for the '51? Also you do not need the large memory model to use xdata
Erik
Your problem is that you're trying to leap into a project before having gained the necessary understanding of the tools.
There are lots of support materials here: http://www.keil.com/support/ including the full set of manuals for the C51 toolset.
Books here: http://www.keil.com/books/8051books.asp
Training: http://www.keil.com/events/links.asp
"i have to use xdata variables so i have to use large memory model"
No, you don't have to.
Read the description of Memory Models again: http://www.keil.com/support/man/docs/c51/c51_le_memmodels.htm
"when we are accessing not more than 256byte of external memory we use pdata"
You can use PDATA - but you don't have to. Also, your hardware needs to be appropriately configured...
"for inernal we use data"
or IDATA.
Note that the terms "internal" and "external" can be misleading in modern devices with on-chip XDATA RAM...
"How to use them in programming"
Please read the manual: http://www.keil.com/support/man/docs/c51/c51_le_memtypes.htm
Thanks, Neil. Mr. Erik is also may be right.
My Problem is:
I want to interface device which communicate through serial communication with uC. I checked this device using serial port analyzer it is responding but when i am giving that commands using uC it is not responding.
if i am accessing memory of that device then i have to use xdata variables so i have to use large memory model thats why i am asking can we use it.
Please guide for this.
It may be right bcoz i does not understand this memory model.
I know that when we use exernal memory we use xdata type. when we are accessing not more than 256byte of external memory we use pdata. and for inernal we use data.
But ? is How to use them in programming. Just specifying data type or something else.
I think you're jumping to a conclusion, there, Erik.
There may be a valid reason for wanting to experiment with different memory models...
... you are about to find out that "the longest route between two points is a shortcut you don't know"
jumping into the large model while evaluating, show that you have not taken the time to familiarize yourself with the processor architecture before starting.
Yes.
http://www.keil.com/demo/limits.asp
But do note that it's not just variables that are affected by the Memory Model:
http://www.keil.com/support/man/docs/c51/c51_le_memmodels.htm
Can? Want? Need?
You want to look at the generated code? Because the code size limitation means you will never be able to build a project large enough to need the large memory model. On the other hand - a developer can build huge projects without a need for the large memory model...
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