what's the issue when implementing USB MSC on ipod 3rd gen?
where can i get further info.?
I think the issue is that no one has worked on it. You can check /firmware and /firmware/target/arm to compare whats been done for PP5002 to PP502X (which has working USB). I don't know how similar they are.
I just read the brief datasheet (4 pages) of PP5002 and PP5020. I observed the PP5002 only intergrated a USB 1.1 controller, while the PP5020 intergrated a USB 2.0 host and device controller. But the Ipod 3gen absolutely has a USB 2.0 controller, because I can transmit file @ 14MB/s. So I concluded ipod 3gen had an external USB 2.0 controller.
I wonder if there is any detailed datasheet of PP50xx, and detailed document or photo of the ipod 3gen.
------------------------------------------------------
I found the detail of ipod 3G in ipodlinux.
http://www.ipodlinux.org/wiki/GenerationsAnd the ipod 3G has a Cypress Semi CY7C68013-56LFC USB2.0 MCU as USB controller. I went through the datasheet and concluded when power-on, PP5002 will download the "Firmware of USB" to CY7C68013 via I2C bus, and the E8051 core on CY7C68013 will run the "Firmware of USB" and communicate with PP5002.
As the communicate protocol is not an open one, if we want to use it , we must code another "Firmware of USB".