Chapter 1: Beginnings
Chapter 2: Further Beginnings
Chapter 3: Hello World
Chapter 4: More On GPIO
Chapter 5: Interrupts
Chapter 6: More On Interrupts
Chapter 7: Timers
Chapter 8: Adding Some Real-World Hardware
Chapter 9: More Timers and Displays
Chapter 10: Buttons and Bouncing
Chapter 11: Button Matrix & Auto Repeating
Chapter 12: Driving WS2812 RGB LEDs
There are 2 messages in this thread.
You are currently looking at messages 1 to 2.
So far in April, you have voted 0 times ou of a total of 0 votes by the community.
Please help us clean the archives from unuseful discussion threads by using the voting system! Details here.
Hi, I have a query on USB remote wakeup. While the device performs resume signalling for ~1-15msec which wakes up the hub and inturn the host. What if there are multiple resume signalling's initiated from the device when the hub/host is already up ? Will those consecutive resume signalling be ignored from host ? Kindly let me know your valuable inputs. Regards, Sandeep --------------------------------------- This message was sent using the comp.arch.embedded web interface on http://www.EmbeddedRelated.com
On Sun, 06 Dec 2009 23:32:16 -0600, Sandeeptssmg wrote: > Hi, > I have a query on USB remote wakeup. While the device performs resume > signalling for ~1-15msec which wakes up the hub and inturn the host. > > What if there are multiple resume signalling's initiated from the device > when the hub/host is already up ? > > Will those consecutive resume signalling be ignored from host ? According to USB 2.0, section 220.127.116.11 Resume: A device with remote wakeup capability may not generate resume signaling unless the bus has been continuously in the Idle state for 5 ms (TWTRSM). This allows the hubs to get into their Suspend state and prepare for propagating resume signaling. The remote wakeup device must hold the resume signaling for at least 1 ms but for no more than 15 ms (TDRSMUP). At the end of this period, the device stops driving the bus (puts its drivers into the high-impedance state and does not drive the bus to the J state). So, multiple resume signaling is not allowed. The resume 'K' signaling from the device may interfere with data coming from the hubs/host, and lead to errors.