Host Controller Data Manual

4–5
4.2 GUID ROM Register
The GUID ROM register is used to access the serial ROM, and is only applicable if bit 24 (GUID_ROM) in the OHCI
version register (OHCI offset 00h, see Section 4.1) is set. See Table 4–3 for a complete description of the register
contents.
Bit 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Name GUID ROM
Type RSU R R R R R RSU R RU RU RU RU RU RU RU RU
Default 0 0 0 0 0 0 0 0 X X X X X X X X
Bit 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Name GUID ROM
Type R R R R R R R R R R R R R R R R
Default 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Register: GUID ROM
Type: Read/Set/Update, Read/Update, Read-only
Offset: 04h
Default: 00XX 0000h
Table 4–3. GUID ROM Register Description
BIT FIELD NAME TYPE DESCRIPTION
31 addrReset RSU
Software sets this bit to reset the GUID ROM address to 0. When the TSB12LV26 completes the reset,
it clears this bit. The TSB12LV26 does not automatically fill bits 23–16 (rdData field) with the 0
th
byte.
30–26 RSVD R Reserved. Bits 30–26 return 0s when read.
25 rdStart RSU
A read of the currently addressed byte is started when this bit is set. This bit is automatically cleared
when the TSB12LV26 completes the read of the currently addressed GUID ROM byte.
24 RSVD R Reserved. Bit 24 returns 0 when read.
23–16 rdData RU This field represents the data read from the GUID ROM.
15–0 RSVD R Reserved. Bits 15–0 return 0s when read.