First, I'm mostly an analog engineer just now getting into microcontroller design. I'll be using the XC167 and am have trouble finding external memory. I have 12MB of external memory area and am therefore looking for 12MB of memory. Ive been looking for synchronous DRAM but can only find 64MB and greater. Does anybody have recommendations for external memory?
no, I am not refrring to the HUGE memory type. I am saying that, if you need 12MB you have an extremely unusual application for this processor. So, since you just say "I want 12MB", not a word about why, I question that you need it. So much data in volatile memory is just inconceivable. How much code memory do you plan on? Erik
Perhaps you are referring to a huge memory type. A huge pointer is similar to a far pointer but a huge pointer will let you reach farther than a far pointer and can be used to access a larger chunk of memory. I'm not sure what that has to do with suitability of the chosen processor. Perhaps if you can give a specific reason why 12Mbytes of RAM is too much for processor with 16Mbytes of address space we could have a more intelligent debate. -Walt
my happiness does not matter, however for the "167 class" 1MB is considered HUGE and that, of course maks me very puzzled when you talk about 12MB. Erik
"what is the likelyhood of someone, that does not even know that the 167 can not use DRAM, succesfully coding something that need 12 MB ?" I am a Hardware Engineer being given requirements by software as far as how much memory. And as I said in my opening statement, I am mostly an analog engineer getting into designs including microcontrollers. Are you happy now?
The XC167 is a fairly powerful 16-bit processor. It is not inconceivable to imagine this processor working on applications requiring 12Mbyte of RAM. "inconceivable", no likely not either. NOW I ask you "what is the likelyhood of someone, that does not even know that the 167 can not use DRAM, succesfully coding something that need 12 MB ?" Erik
Thanks guys! We may not need all 12Megs but we want it there during development and as an option during production. As far as DRAM goes, I thought self-refreshing DRAM would work. However, I cant find anything less than 64Meg anyway. I'm assuming there are other people further along in their development that would have researched the memory available and could save me some time in maybe finding the best price etc........Anyone?
ONCE MORE if you need 12Mbyte, you have chosen the wrong processor Here we go again! The XC167 is a fairly powerful 16-bit processor. It is not inconceivable to imagine this processor working on applications requiring 12Mbyte of RAM. It's unfortunate that you don't even attempt to learn more about an application before dismissing the designers choice of components. -Walt
The 166/XC16x architecture has 16MB address space. So 12MB is just fine. However it should be static SRAM (since the CPU does not offer a DRAM interface). Reinhard
Yeah I know 12M is an odd number but I thought maybe someone is making it. ONCE MORE if you need 12Mbyte, you have chosen the wrong processor Why do I need SRAM? DRAM is cheaper because this chip does not have a refresh controller. Erik
Yeah I know 12M is an odd number but I thought maybe someone is making it. Why do I need SRAM? DRAM is cheaper.........
1) you need static memory not DRAM 2) if you need 12Mbyte, I think you are in deep doo-doo Erik
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