APPENDIX A MIPS III INSTRUCTION SET DETAILS
Preliminary Users Manual S15543EJ1V0UM 561
SW Store Word SW
base

SW

1 0 1 0 1 1 rt offset

31 26 25 21 20 16 15 0
655 16
Format:
SW rt, offset (base)
Description:
The 16-bit
offset
is sign-extended and added to the contents of general register
base
to form a virtual address.
The contents of general register
rt
are stored at the memory location specified by the effective address.
If either of the two least-significant bits of the effective address are non-zero, an address error exception occurs.
Operation:
32 T: vAddr ((offset15)16 || offset15...0) + GPR [base]
(pAddr, uncached) AddressTranslation (vAddr, DATA)
pAddr pAddrPSIZE - 1...3 || (pAddr2...0 xor (ReverseEndian || 02))
byte vAddr2...0 xor (BigEndianCPU || 02)
data GPR [rt]63 8 * byte || 08 * byte
StoreMemory (uncached, WORD, data, pAddr, vAddr, DATA)
64 T: vAddr ((offset15)48 || offset15...0) + GPR [base]
(pAddr, uncached) AddressTranslation (vAddr, DATA)
pAddr pAddrPSIZE - 1...3 || (pAddr2...0 xor (ReverseEndian || 02))
byte vAddr2...0 xor (BigEndianCPU || 02)
data GPR [rt]63 8 * byte || 08 * byte
StoreMemory (uncached, WORD, data, pAddr, vAddr, DATA)
Exceptions:
TLB refill exception
TLB invalid exception
TLB modification exception
Bus error exception
Address error exception