USB Superspeed Peripherals

[shka_4635201]

hi.....

in the gpio configuration , how to select period and threshold for above question i.e. for 640x480 @30hz.

[YashwantK_46]

Hello,

Can you please what is the value of PCLK that you want?

Also, please refer to the KBA: Increasing Frequency of Bit-Banged GPIO Clock in EZ-USB® FX3™ - KBA90267

SInce the maximum clock frequency that can be achieved by the GPIO's in FX3 is in order of ~500KHz, we will need to know what is the value of PCLK that you want to use?

Regards,
Yashwant

[shka_4635201]

hii...

PCLK is 25.175Mhz

hsync is 15.7khz and

vsync is 30hz

please mention calculation if poassible

[YashwantK_46 · Accepted solution]

Hello,

You can't generate PCLK using GPIO's since the maximum frequency GPIO's can produce is in the order of ~500KHz,

You can generate PCLK using the GPIF state machine but there can be some synchronization issues between PCLK, HSYNC and VSYNC if PCLK is generated in such a way.

You will have to configure two GPIO's as complex GPIO's for the HSYNC and VSYNC

You can refer to this thread to understand on how to set up complex GPIO's for giving PWM output: generating pwm on fx3 ​

You can go through the SDK example to understand the complex gpio from the path: C:\Program Files (x86)\Cypress\EZ-USB FX3 SDK\1.3\firmware\serialif_examples\cyfxgpiocomplexapp

Regards,
Yashwant

[YashwantK_46]

Hi,

Could you please share what your application is going to be?

What are you going to do with the PCLK, HSYNC and VSYNCH?

Regards,
Yashwant