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?
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
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?
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
"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?
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
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
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
Once again I am not doing the software. There will be a touch screen/LCD, voice recognition, and possibly some DSP algorithms. Right now the software engineer is using the ST equivalent evaluation board with 2Megs of ram and he doesn't have enough memory to add voice recognition. I don't know why, the old version didn't have more than 2 Megs and it worked fine at like 1Mhz.......But he will get what he asks for. Makes no difference to me.
if you need 12MB you have an extremely unusual application for this processor. Nonsense, how about a data logger, is that so unusual? You are stuck in a paradigm and cannot get out. -Walt
Nonsense, how about a data logger, is that so unusual? You are stuck in a paradigm and cannot get out. And you are stuck in not reading posts fully, I said "So much data in volatile memory" Erik
You guys are hilarious......LOL..........Thanks for the info......
Mike you never answered How much code memory? Erik
Dude, Im doing the hardware............Not a software engineer...........I have no Idea.........I'll ask if you really want to know........LOL
code memory and data memory is hardware, one is EEPROM/flash, the other is RAM. Erik
As long as all his memory fits in the 16M address space, how does this help determine if the processor is adequate? You don't seem to care how the code is divided into tasks, the periodic rate of each task and how long each task takes to execute. This is the information is required to help determine if the processor has enough bandwidth. Your first post declares "if you need 12Mbyte, I think you are in deep doo-doo" and you second one "ONCE MORE if you need 12Mbyte, you have chosen the wrong processor". All this based on two facts, 1)He is using the XC167 and 2)he is using 12Mbytes of RAM. Your simplistic approach may work for small applications where all the code is executed in a single task but not all systems are designed that way, in fact I suspect that few if any applications for the XC167 are that simple. -Walt
I am not talking about "simple" tasks, nothing could be farther from my mindset. I am talking about REAL time, not the friggin "real enough" time some think has a place in control apps. The processor group we talk about here are quite sloppy at many things and excellent at others. So called multitasking definitely is not in their area of excellence. If you need 12MB of code, you are either multitasking (bad choice of processor) or having such a mess that you are, indeed in big doo-doo. I know that you can MAKE these processors jump through hoops. That you can drive from NY to LA on a bicycle does not make it the right choice, whereas if you deliver small goods in NY a bicycle is an excellent choice. You evidently are of the school "I like this processor, I WILL use it and MAKE it do what I want". That is your choice, it definitely is not mine. Do not take this as me having anything against it, I will gladly use it if it is the right choice and 12MB makes that very unlikely, albeit remotely poissible. Thus I question the choice, and if you have a problem with me questioning it why do you even read a forum?. Do I state "I think, if this does not offend you, that there is an itty bitty cahnce that you may have chosen wrong, but that is just my opinion" or such wimpy s*** NO. Erik