Rainbow Electronics LM93 - Manual (Page 40)

16.0 Registers
(Continued)
16.3 FACTORY REGISTERS 00h–3Fh
16.3.1 Register 00h XOR Test
Register
Address
Read/
Write
Register
Name
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Default
Value
00h R/W XOR Test RES XEN 00h
Bit Name R/W Default Description
Sleep
Masking
0 XEN R/W 0 The LM93 incorporates an XOR tree test mode. When the test mode is enabled
by setting this bit, the part enters XOR test mode. Clearing this bit brings the part
out of XOR test mode.
N/A
7:1 RES R 0 Reserved N/A
The reserved bits of this register should only be used by the manufacturer for testing of the ASIC.
16.3.2 Register 01h SMBus Test
Register
Address
Read/
Write
Register
Name
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Default
Value
01h R/W SMBus Test 7 6 5 4 3 2 1 0 N/D
This register can be used to verify that the SMBus can read and write to the device without effecting any programmed settings.
16.3.3 Register 3Eh Manufacturer ID
Register
Address
Read/
Write
Register
Name
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Default
Value
3Eh R Manufactur ID 0 0 0 0 0 0 0 0 01h
The Manufacturer ID register contains the manufacturer identification number. This number is assigned by National Semicon-
ductor and is a method for uniquely identifying the part manufacturer.
16.3.4 Register 3Fh Version/Stepping
Register
Address
Read/
Write
Register
Name
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Default
Value
3Fh R Version/Stepping
VER[3:0] STP[3:0]
73h
0 1 1 1 0 0 1 1
The four least significant bits of the Version/Stepping register [3:0] contain the current stepping of the LM93 silicon. The four most
significant bits [7:4] reflect the LM93 version number. The LM93 has a fixed version number of 0111b. For the first stepping of
LM93, this register reads 01110000b. For the second stepping of the LM93, this register reads 01110001b and so on. It is
incrementaly increased for future versions for the silicon. The final released silicon has a stepping of 3h therefore this register
reads 73h.
The register is used by application software to identify which device in the family of hardware monitoring ASICs has been
implemented in the given system. Based on this information, software can determine which registers to read from and write to.
Application software may use the current stepping to implement work-a-rounds for bugs found in a specific silicon stepping.
LM93
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