OMAP GPMC module problem with the multiplex address/databus under a single write

Martin Traedholm

Other Parts Discussed in Thread: OMAP3530

Hello

Im using a OMAP3530 processor and I want to make a write process to external memory on a FPGA. I have setup my system so all the control signal(Chip Select,Adress Valid and Write Enable) have the correct timming. The problem is the multiplexed address/data bus, it change from address to data before the Address Valid have deasserted? Any have some idea. I have a chipscope picture from the FPGA view below. Any ideas would help a lot

over 15 years ago

0 BrandonAzbell over 15 years ago

TI__Guru 64450 points

I would suggest looking at the OMAP3530 Technical Reference Manual (SPRUF98) in Chapter 11.1 for the General Purpose Memory Controller (GPMC) description. This document is found on the OMAP3530 Product Folder.

Specifically, when configured for address/data multiplexed mode, there is a section discussing this in Section 11.1.5.9.1.2 for reads and Section 11.1.5.9.2.2 for writes. In your specific case, the Section 11.1.5.9.2.2 is important as it indicates the GPMC drives the address on the address/data multiplexed bus until WRDATAONADMUXBUS time, then it drives the data. This register field is found in GPMC_CONFIG6_i[19:16]. This field defaults to 0x3 on reset.

0 Martin Traedholm over 15 years ago in reply to BrandonAzbell

Prodigy 40 points

Thank you. I will try this out tomorrow.

Martin

0 elcoach over 15 years ago

Prodigy 20 points

Hello Martin,

I am trying to do some similar things as you did. Could you tell explain your set up to me? How and in which file did you configure your pins and your timing parameters?

Thank you for your help!

0 hyungmin son over 13 years ago in reply to elcoach

Prodigy 10 points

Hello. My name is Hyung-Min Son.

I hope to know the GPMC setting process on the OMAP3530, too.

If you already know the setting process, can you give me some information?

my address is miniim24@naver.com

Thank you in advance

0 Jeff Culverhouse over 13 years ago in reply to hyungmin son

TI__Genius 9190 points

Hello,

It really depends on what you are connecting to the interface. here are a couple of good wiki articles on the GPMC. I would also recommend you reading throught the GPMC section of the TRM for detailed information on how to use this interface.

http://processors.wiki.ti.com/index.php/Tips_for_configuring_OMAP35x,_AM35x,_and_AM-DM37x_GPMC_registers

http://processors.wiki.ti.com/index.php/AM3715/03_Memory_Subsystem

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OMAP GPMC module problem with the multiplex address/databus under a single write