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copied!<p>Looking at the datasheet for that part available here:</p> <p><a href="http://www.keil.com/dd/docs/datashts/philips/lpc2131_32_34_36_38.pdf" rel="noreferrer">http://www.keil.com/dd/docs/datashts/philips/lpc2131_32_34_36_38.pdf</a></p> <p>It doesn't appear to have interfaces for memory mapped external flash or sdram nor does it have an MMU.</p> <p>It does have SPI ports, which could be used to interface to SD cards, EEPROM, or serial flash for off chip storage but these would not be memory mapped, you would have to handle moving code segments in an out, given the very limited ram on that chip, that would be difficult.</p> <p>It may be "enough" that you move data into the external storage and store only code in the on chip ROM, this would simplify your challenge at the expense of increased latency when accessing data. You can also look at using the thumb instruction set, which reduces code size at the expense of some speed as well as having the compiler optimize for code density instead of speed.</p> <blockquote> <p>If not, what do people normally do when they run out of chip space?</p> </blockquote> <p>The unfortunate answer here is you chose the wrong chip for your application and/or need to rethink how your application is architected to make it fit in this chip.</p> <p><strong>EDIT:</strong></p> <p>It also looks like there are some almost pin compatible parts with more resources. The LPC2138 has 512kB of flash and 32kB of ram (in comparison to 64/16 on your part). There are also a couple sizes in between the two available. </p> <p>A quick glance at the pin outs looked like the only difference was a second ADC on board that is multiplexed with some of the other pins. Obviously look into this fully but it looks like you could just swap out to the higher end parts without modifying the rest of the board.</p>

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