You need to read what Rew tried to explain, the STM32 requires an external ULPI chip in order to enable HS on OTG_HS, not all boards have that. The internal PHY is FS-only.
Does your board mount the external ULPI PHY?
Giovanni
USB FS Maximum Throughput
Moderator: RoccoMarco
-
Giovanni
- Site Admin
- Posts: 14893
- Joined: Wed May 27, 2009 8:48 am
- Has thanked: 1202 times
- Been thanked: 997 times
Re: USB FS Maximum Throughput
Thanks, I'd read the section at the end of the data sheet showing the need for an external chip , but I'd forgotten about it.
When the earlier section said it could do HS, I took it at face value. The discovery boards don't have ULPI, it seems only the "EVAL" board has that included and that is a 350 dollar board !
If it is of any use I found this board providing humanly accessible connection to the USB3300 :
http://www.dx.com/fr/p/usb3300-usb-hs-b ... jp8jaHLd34
a relatively cheap solution at ten eurobucks.
When the earlier section said it could do HS, I took it at face value. The discovery boards don't have ULPI, it seems only the "EVAL" board has that included and that is a 350 dollar board !
If it is of any use I found this board providing humanly accessible connection to the USB3300 :
http://www.dx.com/fr/p/usb3300-usb-hs-b ... jp8jaHLd34
a relatively cheap solution at ten eurobucks.
Re: USB FS Maximum Throughput
FYI: I might have made a calculation error. IIRC, there was 150Mbyte per second trhoughput, and I calculated that to be 100% of USB-FS throughput. It seems I made an error, as this is exactly 10% throughput..... Oops.
You can hope to achieve about 1Mbyte per second on 12Mbps USB.
As to the ULPI... The STM is picky about what signals go to the ULPI: There is very little you can configure/choose. So you have to be sure that your board has the ULPI pins available, or that you can make them available. Also, as the signals are a bit fast, you might need to keep the wires short. So if you don't have the "matching" motherboard that this module plugs into, you might get problems if you try to use the standard 20cm dupont wires....
You can hope to achieve about 1Mbyte per second on 12Mbps USB.
As to the ULPI... The STM is picky about what signals go to the ULPI: There is very little you can configure/choose. So you have to be sure that your board has the ULPI pins available, or that you can make them available. Also, as the signals are a bit fast, you might need to keep the wires short. So if you don't have the "matching" motherboard that this module plugs into, you might get problems if you try to use the standard 20cm dupont wires....