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<DIV><FONT face=Arial size=2><SPAN class=postbody>Hello All,
<BR> I had some doubts regarding the Interrupt registers of
the OHCI controller. <BR><BR> There are three Interrupt
Registers as mentioned in the OHCI specs - InterruptStatus, Interrupt Enable and
Interrupt Disable registers. <BR><BR> The values of the
Interrupt Enable and the Interrupt Disable registers should complement each
other...but what we seem to observe here is that when we do the required
settings of the bits sequentially in the Interrupt Disable and then the
Interrupt Enable registers, the values of both the registers appear to be the
same. <BR><BR> Like say we have provided, the values as:
<BR>HC_INTERRUPT_DISABLE - 0x4000003f and HC_INTERRUPT_ENABLE - 0x80000040, the
values when read for both the registers, gives us 0x80000040.
<BR><BR> Is there any issue with the sequencing of the values
written to these registers? Meaning do we need to at first do the writes on the
Interrupt Enable and then on the Interrupt Disable registers? or is the sequemce
followed above okay? <BR><BR> Probably, due to the above
settings, we are not seeing the corresponding bits of the Interrupt Status
register getting set when we attach a device to the USB ports. We repeatedly are
getting a value of 0 for that register in the ISR instead of the value
corresponding to roothubstatus change. <BR><BR> Also, another
things was that, Section 6.5 of the OHCI - 1.0 specs, says that for the
interrupts to get trigerred, we require setting 'The MasterInterruptEnable bit
in HcControl is set to ‘1’.' but there is no such bit in the HcControl register.
Does this refer to the MIE bit of the Interrupt Enable
register? <BR><BR>Thanking you for the help. <BR>With Regards,
<BR>Monisha.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=postbody></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2>=====<BR>Success is a journey, not a
destination.</FONT></DIV></BODY></HTML>