chipKIT® Development Platform

Inspired by Arduino™

writing a library for a really great looking RAM chip???

Created Wed, 09 Jan 2013 01:50:17 +0000 by spencoid


Wed, 09 Jan 2013 01:50:17 +0000

i want to write a library for the Micron memory chip NP5Q128A13ESFC0E this looks like a really useful chip for high speed buffering large amounts of data to be written to SD card. i looked at the data sheet very carefully and at some similar libraries for the Arduino. i am pretty confident that i could figure it out and write the library myself but i have never done this and it is going to be a major effort. i would prefer to hire someone who could do it faster and better than i could. anyone interested? here is the link to the part on digikey from where you can get the datasheet:


Wed, 09 Jan 2013 20:49:29 +0000 is not a RAM chip..


Thu, 10 Jan 2013 00:10:54 +0000

no, it is not conventional RAM. it is non volatile similar to flash but it uses s different technology and does have limited write cycles as does flash. you can read and write individual bytes without erasing a whole page. there are similarities to both RAM and flash. i just called it RAM for convenience. it is a really neat looking chip and i very much want a library for the chipkit uno 32 to use it. are you interested in writing such a library? the instructions for the chip look pretty easy so i am going to try it if no one else does but i would much prefer someone who knows how to do this to do the job well and quickly. if not done gratis, i would like an estimate of the cost to write this library.

P5Q serial PCM combines the benefits of traditional floating gate Flash, both NOR-type and NAND-type, with some of the key attributes of RAM and EEPROM. Like NOR Flash and RAM technology, PCM offers fast random access times. Like NAND Flash, PCM has the ability to write moderately fast, and like RAM and EEPROM, PCM supports bit-alter-able WRITEs (overwrite). Unlike Flash, no separate erase step is required to change information from 0 to 1 and 1 to 0. Unlike RAM, however, the technology is nonvolatile with data retention compared with NOR Flash.


Tue, 15 Jan 2013 17:36:22 +0000

i found the library for an older similar Micron serial flash called SFSPI. made a few mods to it and ran some tests. has anyone else used SFSPI successfully? a couple of problems. bulk erase does not seem to work at all and i can not figure out why. also writing seems to be about ten times as slow as it should be making this worthless for my use. in the SFSPI library page program only writes a single byte so i hacked it to write a full page (64 bytes on the P5Q) and did a benchmark test. it is very slow.

i would like to hear about any success with this library and and know of any extensions or mods to the library especially with respect to the additional features of the P5Q.

i can clean up my test sketch and the mods to the library and post later.