Datasheet
4–5
4.2 GUID ROM Register
The GUID ROM register accesses the serial EEPROM, and is only applicable if bit 24 (GUID_ROM) in the OHCI
version register at OHCI offset 00h (see Section 4.1, OHCI Version Register) is set to 1. 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
Offset: 04h
Type: Read/Set/Update, read/update, read-only
Default: 00XX 0000h
Table 4–3. GUID ROM Register Description
BIT FIELD NAME TYPE DESCRIPTION
31 addrReset RSU Software sets bit 31 to 1 to reset the GUID ROM address to 0. When the TSB43AB23 device completes
the reset, it clears this bit. The TSB43AB23 device 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 bit 25 is set to 1. This bit is automatically cleared
when the TSB43AB23 device 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 contains the data read from the GUID ROM.
15–8 RSVD R Reserved. Bits 15–8 return 0s when read.
7–0 miniROM R The miniROM field defaults to 0 indicating that no mini-ROM is implemented. If bit 5 of EEPROM offset
6h is set to 1, this field returns 20h indicating that valid mini-ROM data begins at offset 20h of the GUID
ROM.