RE: Re: Low voltage I/O for MPC555

There is no data register as such.  You'd have to choose a chip select (0-3) and then write the OR and BR registers for that chip select with your choosen peramters including external address range.  Then when you do an external memory write within that address range, all the relevant EBI pins (address, data, CSx, etc) would drive for several cycles. 
 
Please refer to the memory controller section of the manual.
 
- Allan

________________________________

From: [email protected] on behalf of brockmid
Sent: Thu 14/12/2006 22:27
To: [email protected]
Subject: [MPC500] Re: Low voltage I/O for MPC555



Could anybody tell me what the address of the data register is for 
the EBI? It seems to be a lot more complicated than just writing to a 
data register like it is when writing the GPIO(address 0x306100). Is 
there a special setup that is needed? Thanks for the help.

Brock
--- In [email protected] <mailto:MPC500%40yahoogroups.com> , "Dobbin Allan-r11834" 
<Allan.Dobbin@...> wrote:
>
> The GPIO are 5V. If the LCD interface is such that you can connect 
it
> to the EBI external bus interface and use it as memory mapped I/O 
using
> the chip selects, then the bus signals are all 3.3V.
> 
> - Allan
> 
> ________________________________
> 
> From: [email protected] <mailto:MPC500%40yahoogroups.com>  [mailto:[email protected] <mailto:MPC500%40yahoogroups.com> ] On 
Behalf
> Of brockmid
> Sent: Tuesday, November 28, 2006 11:19 AM
> To: [email protected] <mailto:MPC500%40yahoogroups.com> 
> Subject: [MPC500] Low voltage I/O for MPC555
> 
> 
> 
> Hello,
> Are there any ports that can be used for I/O which are low voltage 
> (i.e. less than 5 volts). Currently I am using GPIO (address: 
0x306100) 
> port but I dont see any option to use this in low voltage mode. I 
am 
> interfacing this micro with an LCD which requires at most 3.3V for 
the 
> data lines. I would like to connect directly to the LCD instead of 
> using bus transceiver chips. Thanks for the help.
> 
> Brock
> 
> 
> 
> 
> 
> 
> [Non-text portions of this message have been removed]
>



 


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