Society of Robots - Robot Forum
Electronics => Electronics => Topic started by: sdavis6736 on November 01, 2008, 05:37:29 AM
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I have some 1G memory chips sitting around after upgrading my computer RAM. I was wondering if there is a way to add this externally to my robot so there is more space for storage or calculations?
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There is always a way... but there should be a common sense too...
Let's think logicaly. I bet you had something like DDR or SDRAM memory. Something like on the picture below. Now, without any knowledge of electronics at all. First, count pins in connector on picture. Now, count pins on your microcontroller. See any difference? I don't even ask which uc you have. Doesn't really matter. Now, let's assume there are enough for one SDRAM chip. Do you have enough skills to desolder one from memory plate? Bet you don't.
And now a little more scientific answer. Depending on your uc type, it may be possible to add external RAM. If your uc have MCU or MMU, it will be even pretty easy to use it. If it doesn't you'll have to interface it manualy, and you will not have any speed advantage with that. But if you had MMU on your uC? Well, if you are using ARM9 for example, I'm pretty sure you wont be asking such questions.
So... Yes, there is a way. But not for everyone and possibly not for you.
(http://www.microlanbh.com/Portals/Default/RAM/SDRAM.jpg)
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http://hubbard.engr.scu.edu/embedded/avr/boards/avrminiv4/quickstart.html that has an SD card slot, no?
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http://hubbard.engr.scu.edu/embedded/avr/boards/avrminiv4/quickstart.html that has an SD card slot, no?
He said about spare "!G memory chips after upgarding RAM" - that is another thing.
Connecting sd/mmc card is no problem at all, just usual SPI interface.
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My bad, should have read the post more carefully.
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There is always a way... but there should be a common sense too...
Let's think logicaly. I bet you had something like DDR or SDRAM memory. Something like on the picture below. Now, without any knowledge of electronics at all. First, count pins in connector on picture. Now, count pins on your microcontroller. See any difference? I don't even ask which uc you have. Doesn't really matter. Now, let's assume there are enough for one SDRAM chip. Do you have enough skills to desolder one from memory plate? Bet you don't.
There is no reason to be so rude. And yes I do have enough skills.
And now a little more scientific answer. Depending on your uc type, it may be possible to add external RAM. If your uc have MCU or MMU, it will be even pretty easy to use it. If it doesn't you'll have to interface it manualy, and you will not have any speed advantage with that. But if you had MMU on your uC? Well, if you are using ARM9 for example, I'm pretty sure you wont be asking such questions.
So... Yes, there is a way. But not for everyone and possibly not for you.
(http://www.microlanbh.com/Portals/Default/RAM/SDRAM.jpg)
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My bad, should have read the post more carefully.
You read the message just fine. Thank you for a great lead and for being a part of this forum. Keep up the great work.
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people chill out with the flame wars ;)
also I don't think more memory would really be necessary. The internal flash of the microcontroller should be more than enough.
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people chill out with the flame wars ;)
I did not mean to insult this forum, I just don't believe that it is right to make rude comments and assumptions about and to others. People are here for help and to share ideas. I have to put up with insults and rude comments at work and I will not accept it anywhere else in my life. I put up with it at work because it allows me to work less than 30 hours a week and affords me time and money to pursue my passion, which is robots.
also I don't think more memory would really be necessary. The internal flash of the microcontroller should be more than enough.
You are right that the internal flash of the microcontroller should be more than enough. I was just thinking of a future project that might be of interest to me. The robot I am working on may need additional memory in the distant future. If the microcontroller I am using has enough ports for my future expansions, I thought memory might be an issue. Thank you for your time and input.
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I heard that every year the amount of data that can be put on a chip is doubled. So as long as your projects dont require exponentially increasing amounts of memory you should be okay ;D
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If it is RAM then the micro will not have enough pins to use 1GB of it. If you want more RAM use an AVR32 (great micros). They even have hardware to connect external RAM like this.
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If it is a module like an sdram board, then all you need to do is look at the actual ram chips installed on it for any writing. Look them up at datasheetcatalog.com and see what the pins do and how to actually work the individual chips. The memory chips that i use have 16 pins for addressing and 8 pins for data then the usual power and ground connections. Follow the pin traces to the connector slots on the board then you can use them individually.
You will also notice a much smaller chip at the far right or the far left of the board, this is an eeprom that contains information like how big the memory module is so when its put in your computer then it can see the size of the ram without having to check through it all.
(you can also buy i/o port extenders, these are usually used through an i2c bus. Basically you send i2c commands to the i/o extender in order to control another 20+ i/o pins. The good thing about i2c is that you can use well over 100 devices over the bus meaning that you can have lots and lots of pins for integrating ram).
This is slower than using the built in ram on an mcu, plus you'll have to develope a memory managment system but computers are like this anyway...
The ram chips that i have are dip style that i bought individually, but the concepts are the same.
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Thank you paulstreats for taking the time to give me this info. I appreciate it. It will be a great help when I get to this part of my project.