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Message
From: midas@j...
Date: Thu, 2 Oct 2003 10:06:32 +0200
Subject: [usb] HOW TO Clear STALL condition?
Hi,
I'm a newbie to USB and USB mass storage devices.
I have a little trouble with my Cypress SL811HS Host Controller.
I've got the device to enumerate and I've found all of it's endpoints and
I'm able to send CBW's to the bulk OUT endpoint and read my data from
the IN endpoint as well as getting my CSW out from the IN endpoint.
For certain commands like INQUIRY and REQUEST SENSE I have already
been able to execute in the following sequence..
1. Send CBW to bulk OUT endpoint
2. Read DATA from bulk IN endpoint
3. Read CSW from bulk IN endpoint.
For commands like READ_10 and READ_CAPACITY use sequence above.
The device WILL be stalled by host.
Is this STALL just a handshaking message to differentiate a data
transfer from a CSW transfer? And how to clear this STALL condition?
I approciate your help.
i.e.
Read_Capacity
Host Device
OUT_CBW ->
In ->
<- Data(1st)
In ->
<- Data(2nd)
In ->
<- Data(3rd)
In ->
<- Data(4th)
In ->
<- Data(5th)
In ->
<- Data(6th)
In ->
STALL -> //How to clear this stall message
//and continue getting the following
//data?
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