Avago Technologies LSI53C1010 - Manual (Page 166)

6-16 Using the Registers to Control Chip Operations
0x46 MACNTL 3, 2, 1, 0 Initialize these when using the MAC_TESTOUT pin. These bits
determine local or remote access for the following operations:
Bit 3: Data write
Bit 2: Data read
Bit 1: SCRIPTS pointers
Bit 0: SCRIPTS fetch
0x48 STIME0 [7:4], [3:0] Bits [7:4]: Handshake-to-Handshake Timer Period
Bits [3:0]: Selection Time-Out
0x49 STIME1 [3:0] Bits [3:0]: General Purpose Timer Period
0x4A RESPID0 all N/A
0x4B RESPID1 all N/A
0x4D STEST1 7, [3:2] Bit 7: SCLK
Bits [3:2]: SCSI Clock Doubler 1–0 (LSI53C875 only)
0x4E STEST2 5, 1 Bit 5: SCSI Differential Mode
Bit 1: Extend REQ/ACK Filtering
0x4F STEST3 7 Bit 7: TolerANT Enable
0xBC SCNTL4 7 Bit 7: Ultra3 Transfer Enable
Table 6.10 LSI53C825A/875/876/885/895/895A/896/10XX Startup Bits (Cont.)
Register
Address Register
Name Bits Remarks