Re: [linux-sh:01761] RE: [linuxsh-dev] SH4 hardware problem

[<bar...@ya...>]

Hi Dustin:

Thank you for help

The RDY pin is high and being pulled high by a
resistor. The CPU does seem like it is waiting for
something?? Since the chip sits on the first byte (I
have 8bit Flash memory for area 0), this means that
the CPU has not yet read the first instruction.
Therefore, the cpu basically sits on the resetted
state.

Mark

 --- Dustin McIntire <du...@se...> wrote: > Hi
Mark,
> I don't know about the SH7750, but the SH7751 has a
> RDY# pin that forces the
> processor to stall indefinately waiting for the bus
> cycle to complete.  You
> may want to check this and make sure it is not
> asserted (ie make sure it is
> logic high).  There should be and external pullup
> resistor on this pin as
> well.
> 
> Dustin.
> 
> -----Original Message-----
> From: lin...@li...
> [mailto:lin...@li...]On
> Behalf Of Barkuson
> Sent: Wednesday, July 04, 2001 6:43 AM
> To: lin...@m1...;
> lin...@li...
> Subject: [linuxsh-dev] SH4 hardware problem
> 
> 
> 
> Hi,
> 
> Firstly, my apologies for sending this mail if this
> is
> not relevent to the mailing list. However, this is
> quite urgent, sorry. Could any hardware people help
> me
> out please?
> 
> I have a custom Sh4 (SH7750) board which has not
> been
> able to run :(. Everything looks alright except that
> the board boots up and sits at address 0x00000000
> (the
> data at this address in the flash memory is on the
> data bus). The CPU seems to halt at this point with
> the following board status,
> 
> - both main crystal and rtc crystal running
> - both status pin at low level
> - all NMI and IRL pins pulled up
> - BREQ pulled up
> - address sits at 0x00000000 and does not increments
> - CS0 low
> - RD low
> - all WE high
> 
> Is there anything else that I should check?? or any
> setting that I could be missing??
> 
> Can anyone direct me to a right place??
> 
> All helps are greatly appreciated.
> 
> Mark
> 
> 
>
____________________________________________________________________________
> _
> http://messenger.yahoo.com.au - Yahoo! Messenger
> - Voice chat, mail alerts, stock quotes and
> favourite news and lots more!
> 
> _______________________________________________
> linuxsh-dev mailing list
> lin...@li...
>
http://lists.sourceforge.net/lists/listinfo/linuxsh-dev
>  

_____________________________________________________________________________
http://messenger.yahoo.com.au - Yahoo! Messenger
- Voice chat, mail alerts, stock quotes and favourite news and lots more!