confusion about which one is the host between 89s52 and PC (usb communication)

[cmjauto]

Hello Everyone,
I have a problem when analyzing the communication code between PC, PDIUSBd12 and 89s52 microcontroller.

confusion 1: why PDIUSBD12 need a MCU(such as 89S52) to implement USB communication? That is : What's the role of 89s52 in the system?

confusion 2: When i analyze some code, it seems that it is the 89S52 that acts as the host role rather than the PC, So i fall into confusion again whether 89S52 is a host or PC is. This confusion may be a result of confusion 1.

Can anyone help me to clarify this conceptual confusion, thanks in advance!

Best regards!

 

[hemnath]

Think your micro-controller 89S52 has inbuilt USB capabilities?

If answer is NO, then you have to look for external device for usb communication. That's the reason PDIUSBD12 pheripheral is added to MCU.

Best wishes

 

[cmjauto]

Thank you for your kind reply.
The 89S52 has no USB capabilities. Here i also want to know what's the function of the MCU and PDIUSBD12 in the context of USB communication system. Is there any fundamental description(web links or documents) about them? I think i need a systematic learning about these, thank you very much!

Think your micro-controller 89S52 has inbuilt USB capabilities?

If answer is NO, then you have to look for external device for usb communication. That's the reason PDIUSBD12 pheripheral is added to MCU.

Best wishes

 

[hemnath]

Lets say, If you want to transmit the data from your micro-controller to PC using USB communication. And, your 89S52 has no USB capabilities. But still you like to do USB communication with 89s52, philips has a pheripheral called PDIUSBD12 to satisfy usb communication.

Here i also want to know what's the function of the MCU and PDIUSBD12 in the context of USB communication system

MCU will hold the data and transmit to PDIUSBD12. This PDIUSBD12 will then send the data to your PC.
You can send the data directly to your PC if you have usart in your micro-controller.

Best wishes

 

[cmjauto]

Thank you for your patient answers.
I think i have a long way to go.