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Message
From: wesselin@n...<wesselin@n...>
Date: Wed May 12 18:37:14 CEST 2004
Subject: [usb] UTMI speed negotiation troubles...
Hello all,i'm rewriting mr. Usselman's UTMI interface so it can interface to a
philips ISP 1501-01 transceiver. I'm having trouble getting the host to
recognise the device.
After a connect, the device evaluates the linestate after a debounce
period of 100 ms,
The host signals suspend,
device suspends and looks for a reset or a suspend,
host signals reset,
device drives a K,
The host responds with a JK sequence.
Here the problem starts:
not only does the host begin to signal the sequence after several
milliseconds (as opposed to a 100 us per spec), the duration of the J's
and K's is too short and has gaps....
well, not responding to the sequence makes no sense, so i'm giving it a
go and put the transceiver in High speed mode.
After 3 ms of inactivity the device detects that the Host ignorantly
signals a suspend........
after being suspended for a while the host drives a reset,
speed negotiation starts all over again and blah blah the whole story
repeats itself:
host responding way too late and the J's and K's being too short.
end of story is that after 3 speed negotiation try's the host gives up
and keeps the port suspended..........
Does anybody care to give me some pointers in this matter or is
anybody experiencing the same problems..........?
Regards,
Egwin Wesselink
This transceiver has the cumbersome "feature" of not being able to
evaluate the linestate signal when in high speed modus.
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