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Hi all
I need a counter to to count up something
So I use follow code to do this work
unsigned long pdata counter[4]={0,0,0,0};
in the counting place,
counter[0]++;
when run finsih , I print the result
printf(%ld\n",counter[0]};
Maybe I have run to 1000 times ,so counter[0] value
will be to 1000 , but the printf result maybe very
large, like as 92343421;
why ?? how can I make sure to count up correctly??
Thanks a lot
best regards
Thanks for you relpy
it is almost realy code I use , I just add that code in every where that I need to counting up
Other code is need HW to work ,so I didn't use any Simulator or debugger ,just printf infomation only
How do I to mark sure your PDATA is working & correctly configured? any infomation I can check??
I thank ulong is 32bit , but 8051 is 8 bit , maybe just like you say , pdata is not working correctly
the counter value maybe very large ,so will be round 0xfffffff--->0x000000000
Sometimes the printf value is correct , sometimes is samll number ,but print big number
FYI
"it is almost realy code I use"
Almost - but not exactly.
"Almost" is not good enough - how do you know that it's not precisely that (possibly subtle) difference that causes the problem?!
"How do I to make sure your PDATA is working & correctly configured? "
My PDATA is irrelevant - you are the one that's observing the problem, so it's your PDATA that is concerned; ie, the PDATA in the target hardware that you are using.
Do you actually understand how PDATA works?
On some chips, XDATA and/or PDATA have to be sepcifically enabled and/or configured. Some chips possibly don't suppotr it at all...
"any infomation I can check??"
check in the chip's Datasheet.
"I think ulong is 32bit"
Don't just "think" - look it up in the compiler Manual and know for sure! http://www.keil.com/support/man/docs/c51/c51_ap_datastorage.htm
"maybe just like you say, pdata is not working correctly"
Try moving the variable to DATA or IDATA - if the problem then goes away, that strongly suggests a problem with (or, at least, related to) PDATA...
I have more question ^^"""
My chip is similar to the DS80C320 in terms of hardware features and instruction cycle timing
1 Can I use "pdata" specifier in the large memory model??
The Keil Doc say "The pdata memory type specifier refers to only one (1) page or 256 bytes of external data memory"
I have 8k external ram and I see the MAP file
XDATA 0000H 0044H INPAGE ?PD?MYTEST XDATA 0044H 0240H UNIT ?XD?MYTEST XDATA 0284H 0073H UNIT _XDATA_GROUP_ it seems look like ok
2 when I use KEIL IDE to run ,I can't see the variable value is the watch windows, why??
"My chip is similar to the DS80C320"
What what is the chip, exactly? Manufacturer name, nad Full part number with all suffix and prefix letters/digits?
"Similar" doesn't help - even if there is only one small difference, that could be the one that stops your code from working, couldn't it?!
How about providing a link to the Datasheet.
"1 Can I use 'pdata' specifier in the large memory model??"
Of course you can - the Memory Model simply specifies the default to be used in the absence of a specific memory space specifier.
However, my earlier question still remains: Do you actually understand how PDATA works?
And, are you certain that the PDATA implementation on your hardware is correct & working?
sorry ,my chip is ASIC IP only, So it is datasheet just say it like as DALLAS DS80C320
http://www.keil.com/dd/chipinfo.asp?did=2975&bhcp=1
I didn't know pdata too much , I just studing ^^"""
There is no startup.a51 in my code , do I need to modify this file to use PDATA??
"my chip is ASIC IP only"
In that case, it is very likely that it handles PDATA in a special way - or may not support it at all. If the datasheet doesn't mention it, you need to ask the IP provider specifically about this.
"I didn't know pdata too much"
Don't try to use it until you really understand it, and how (if at all) it is implemented on your target.
Get your code working first using DATA, IDATA, or XDATA.
"There is no startup.a51 in my code , do I need to modify this file to use PDATA??"
Yes!