[U-Boot-Users] IDE access swaps the bytes.

Travis B. Sawyer tsawyer+u-boot at sandburst.com
Fri Dec 3 14:44:12 CET 2004

Helio Fujimoto wrote:

 >it is attached directly to the bus. There is an FPGA which is controls 
 >IDE interface. The IDE data bus [0-15] is connected to the MPC855T 
data bus [15-0].

Ah.  We also have CF direct to local bus....
Here's how we connected it so as to keep common code common:

PER_DATA8     <->   CF_DATA15
PER_DATA9     <->   CF_DATA14
PER_DATA10   <->   CF_DATA13
PER_DATA11   <->   CF_DATA12
PER_DATA12   <->   CF_DATA11
PER_DATA13   <->   CF_DATA10
PER_DATA14   <->   CF_DATA9
PER_DATA15   <->   CF_DATA8
PER_DATA0   <->   CF_DATA7
PER_DATA1   <->   CF_DATA6
PER_DATA2   <->   CF_DATA5
PER_DATA3   <->   CF_DATA4
PER_DATA4   <->   CF_DATA3
PER_DATA5   <->   CF_DATA2
PER_DATA6   <->   CF_DATA1
PER_DATA7   <->   CF_DATA0

Since you're running directly from 855T local bus and not from your fpga,
you're in for some rewiring.  If, however, your data lines run through 
your fpga,
you can simply reprogram the pins.

Good luck,

ps:  I just switched from Evolution to Thunderbird, I hope this is plain 
text only!

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