lpcware

LPC1778 test code for SDRAM

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by Krzysiek N on Tue Aug 11 01:39:05 MST 2015
I have prepared a PCB with LPC1778 (FBD208) and SDRAM AS4C4M16S-7TCN

http://www.alliancememory.com/pdf/dram/64m-as4c4m16s.pdf

and I’m a locking for some program to test it with EMC controller, I have found some sample code for Keil and different SDRAMs:

https://www.lpcware.com/content/nxpfile/lpc177x-and-lpc178x-cmsis-compliant-standard-peripheral-firmware-driver-library-keil

but the EMC doesn’t work properly for me, DATA bus signals are very poor doesn’t reach 2V level and are almost triangle, it Look like there is no push pull output or pullaps are very week. SDRAM is under LPC on the PCB BOTTOM side and is connected to LPC according NXP specification, connections are short and it’s not a tracks capacity issue.

I’m asking You for some test code for this memory or any sample code for LPC1778 (Keil project or hex file) with similar SDRAM with properly initiated EMC.

Thank You!

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