OCM BRAM and PCC issues...

Hello All,

I am using Virtex II pro for a design with PPC,Timer,
Bram, OCM, PLB,OPB. The Bram is attached on the OCM bus. I have done
the Bram's PORT_B ports as external in order to load a stimuli vhdl
file(as testbench) in order to load address and data and then these to
be read through Port_A from the PPC. I came along some problems that i
cannot find the answers.

My bram is 32x32. The data and the address is 32 bits long. A part of
the code is:

Bram_WEN_B_pin <= transport ("1111");
Bram_Addr_B_pin <= transport
std_logic_vector' ("00000000000000000000000000000001) ---address
location 1
Bram_Dout_B_pin <= transport
std_logic_vector' ("00000000000000000001000100010001) -- data 1111

(a) Should all the 4 bits of the WEN_B be always all ones when
writing?
(b) The address locations i am writing are from 0-15, ( total range
0-255). These BRAM locations migth be captured by other IPs?
(c) The address portA and PORT B of the DSOCM/ISOCM Bram becomes as UUUU0101010UUU..blablbla. ok
these are from (8:29) range but the UUU from where these bits are
filled?
(d) I cannot find the flag bit that the PPC sends back to the BRAM at
the address point 16 so from there i can read the flag and load new
data after an interval of time.

thank you very much.

regards