C6678 NAND Write Speed

Hi,

I test the evm6678l nand write speed via NandWriteDataBytes(), and the result is about 300KB/s which is far from the chip program speed.

My questions are:

1. how to improve the program speed ?

2. the NAND device（Numonyx NAND512R3A2DZA6E） on the evm has the page size of 528 Bytes. Replacing it with a large page size NAND may help improving the program speed. Could Ti provide a alternative NAND device which has full pins compatibility ?

Regards,

over 13 years ago

0 Bill Taboada over 13 years ago

TI__Mastermind 42545 points

The EMIF interface in the C6678 was not designed to be a high speed memory interface and the driver wasn't optimized for speed. In addition the hardware support for ECC in the NAND controller is limited to smaller pages. It supports 1-bit ECC calculations for 512Bytes and 4-bit ECC calculations for 518Bytes. If you use a NAND with a larger page size you will have to implement your ECC calculation in software which will add some overhead.

0 dp over 13 years ago in reply to Bill Taboada

Intellectual 990 points

Does Ti support the ECC calculation algorithm in software?

If not, where can I get it ?

Regards,

0 Bill Taboada over 13 years ago in reply to dp

TI__Mastermind 42545 points

ECC calculation in software for NAND should be included in the August release of the MDSDK software.

0 dp over 13 years ago in reply to Bill Taboada

Intellectual 990 points

Thanks Bill,

Does the ECC calculation in software support 8-bit ECC or more bit ECC ?

Regards,

0 Renjith Thomas over 13 years ago in reply to dp

Guru 31670 points

DP,

Are you looking for NAND r/w performance improvement? I have not done NAND throughput improvement in DSP platform, but I have got performance improvement for NAND in Davinci and OMAP platforms. I got upto 8 MB/sec read and 3.8 MB/sec write throughput in other platforms. I might be able to help you here, if you are seriously trying to improve NAND performance here.

0 dp over 13 years ago in reply to Renjith Thomas

Intellectual 990 points

Renjith,

I have two targets:

1. C66 support large-size NAND, such as 16GB;

2. improve the NAND write speed, 3.8MB/s could be acceptable.

Regards,

0 Renjith Thomas over 13 years ago in reply to dp

Guru 31670 points

DP,

1. Are you planning to interface SLC NAND or MLC? If it is MLC then I don't think 4-bit ECC will be sufficient, as MLC is more prone to errors.

2. I can help you with NAND optimization. Please contact me @ renjith.thomas@pathpartnertech.com

0 dp over 13 years ago in reply to Renjith Thomas

Intellectual 990 points

Hi,

No matter slc or mlc, the large capacity is the key point. The 4-bit ECC of EMIF limint the capacity of NAND. So I ask if TI support the ECC algorithm software.

Regards,

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C6678 NAND Write Speed