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USB Superspeed Peripherals

LuTa_4642501
New Contributor II

Hi,

I'm using cyfxusbi2sdmamode.c example. It configures uart and i2s.

Where this uart is located ?

- Some virtual uart through USB3 cable into my Host ?

- Or it the one exposed by micro usb jtag cable ?

The code says:

    /* Configure the IO matrix for the device. On the FX3 DVK board, the COM port

     * is connected to the IO(53:56). So since we need to use both I2S and UART,

     * configure the GPIF bus to be 32 bit. This does not mean that the GPIF has

     * to be in 32 bit configuration, it just means that the whole 32bit shall be

     * reserved for the GPIF interface and not available for GPIO. Another option

     * is to not use UART, and use I2S_ONLY mode or use an external UART controller

     * on the IO(46:49). */

Where is this IO(53:56) ? Can you explain what is IO(53:56) ?

Looking at "SuperSpeed Explorer Kit Schematic.pdf" I can't find IO(53:56).

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1 Solution
JayakrishnaT_76
Moderator
Moderator

Hello,

UART is used for sending the debug information to the host through a USB 2.0 cable. This is done by making use of a USB-Serial Converter chip as shown in page 8 of the SuperSpeed Explorer Kit Schematic.

IO(53:56) refers to GPIO 53:56 of the FX3 chip. Please find the pin description for FX3 chip at page 15 of the FX3 Datasheet. The link to the same is given below:

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

From this, you can understand that when the GPIF bus width is configured to be 32 bits (as done by this example project), GPIO 53:56 can be used as COM port. If the GPIF data bus width is configured to be 16 bits, then depending on the io_cfg.lppMode, GPIO 53:56 can be used as UART/SPI.

Best Regards,

Jayakrishna

Best Regards,
Jayakrishna

View solution in original post

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1 Reply
JayakrishnaT_76
Moderator
Moderator

Hello,

UART is used for sending the debug information to the host through a USB 2.0 cable. This is done by making use of a USB-Serial Converter chip as shown in page 8 of the SuperSpeed Explorer Kit Schematic.

IO(53:56) refers to GPIO 53:56 of the FX3 chip. Please find the pin description for FX3 chip at page 15 of the FX3 Datasheet. The link to the same is given below:

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

From this, you can understand that when the GPIF bus width is configured to be 32 bits (as done by this example project), GPIO 53:56 can be used as COM port. If the GPIF data bus width is configured to be 16 bits, then depending on the io_cfg.lppMode, GPIO 53:56 can be used as UART/SPI.

Best Regards,

Jayakrishna

Best Regards,
Jayakrishna

View solution in original post

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