QUARTUS 4.2 NIOS 1.1 UPDATE PROBLEM

the adress lines are connected as follows

CPU A[9..2] to

8-BIT SLAVE A[7..0]

BASE 0x903000

correct behavior should be (is with Quartus 4.1 Nios 1.0) :

function systemadd(CPU) add at slave

IORD(BASE,0x00) 0x????00 0x00

IORD(BASE,0x01) 0x????04 0x01

IORD(BASE,0x02) 0x????08 0x02

IORD(BASE,0x03) 0x????0C 0x03

..

IORD(BASE,0x10) 0x????40 0x10

wrong behavior is (measured):

function ldwio r2,0(r2) systemadd(CPU) add at slave

IORD(BASE,0x00) r2=0x903000 0x????00 0x00

IORD(BASE,0x01) r2=0x903004 0x????01 0x00

IORD(BASE,0x02) r2=0x903008 0x????02 0x00

IORD(BASE,0x03) r2=0x90300C 0x????03 0x00

IORD(BASE,0x04) r2=0x903010 0x????04 0x01

(by debugging assembly code, i can see that r2 has the correct value before

ldwio)