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USB superspeed peripherals Forum Discussions

WGT_4383351
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Two CYUSB3KIT-003 stacked, each connected to PC host, what is the best bulk transfer rate?

My calculate: 100MHz*16bit bus=200MB/s with like 10-20MB/s overhead loss, can this be achieved?

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JayakrishnaT_76
Moderator
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First question asked 1000 replies posted 750 replies posted

Hello,

When you are using 16bit GPIF at 100MHz, the theoretical maximum throughput is 200MBps. Practically, the throughput will be slightly lesser due to the overhead. Practical bandwidth is around 180MBps.

Best Regards,

Jayakrishna

Best Regards,
Jayakrishna

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JayakrishnaT_76
Moderator
Moderator
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First question asked 1000 replies posted 750 replies posted

Hello,

When you are using 16bit GPIF at 100MHz, the theoretical maximum throughput is 200MBps. Practically, the throughput will be slightly lesser due to the overhead. Practical bandwidth is around 180MBps.

Best Regards,

Jayakrishna

Best Regards,
Jayakrishna
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Will 100MHz work when connect two CYUSB3KIT-003 together considering the impact of signal integrity from the DIP headers and long trace lengths?

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Hello,

We have not seen any issues in that configuration.

Best Regards,

Jayakrishna

Best Regards,
Jayakrishna
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BTW in the document "Document No. 001-75705 Rev. *I " , is "Arm9" better written as "ARM9"?

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Hello,

Thank you for the suggestion. We will evaluate your query and do the needful.

Best Regards,

Jayakrishna

Best Regards,
Jayakrishna
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In CYUSB3KIT-003 the full GPIF II are wired to the headers, then could 32bit bus be used? If not, then while 32bit are wired out? Is the 16 unusable data bus wired out only for probing?

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Hello,

GPIF II block on FX3 supports 8,16,24 and 32 bit data bus. While you configure the data width to a particular value, the remaining pins on the board can be used as that mentioned in table 7 of FX3 datasheet. The link to the document is given below:

https://www.cypress.com/file/140296/download

You can customize the data bus width required for the application using GPIF II designer tool which comes along with FX3 SDK. The user guides for using this can be found in the following location:

C:\Program Files (x86)\Cypress\EZ-USB FX3 SDK\1.3\doc\GPIFII_Designer

Note; This path depends on the installation directory of FX3 SDK.

Best Regards,

Jayakrishna

Best Regards,
Jayakrishna
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In on this doc https://www.cypress.com/documentation/application-notes/an87216-designing-gpif-ii-master-interface I found that the official reference way to stack two CYUSB3KIT-003 is using 32bit bus which gives amazing ~400MB/s speed. Figure 25 in that doc show this fact only in a floating tool tip window, I didn't notice that before and thought the reference design only use 16bit bus.

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