LPC1778 test code for SDRAM

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LPC1778 test code for SDRAM

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lpcware
NXP Employee
NXP Employee
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-firm...

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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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by Krzysiek N on Thu Aug 13 23:37:12 MST 2015
Thanks for answer, Clkout0 is 60MHz address line signals are ok, only DATA signals are strange, I have found some sample code from embedded artist, voltage level is now ok but rising is to slow please check attached file for details. Maybe someone have some full checked code it can be a hex file to prevent from faulty compilation.
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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by mc on Tue Aug 11 08:32:03 MST 2015
Hi Krzysiek N,
What is the SDRAM clock frequency frequency? It can not be beyond 80MHz. Also I would recommend you to use more supported LPCopen plateform. Please see below.
https://www.lpcware.com/content/nxpfile/lpcopen-software-development-platform-lpc17xx-packages

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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by wmues on Tue Aug 11 07:28:57 MST 2015
SDRAM infos
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