JAJSOK5Q March 2011 – March 2024 TUSB7320 , TUSB7340
PRODUCTION DATA
The Serial Bus Control and Status register is used to control the behavior of the Serial bus interface. This register also provides status information about the state of the serial bus. This register is reset by a PCI Express reset (PERST#), a GRST#, or the internally-generated power-on-reset.
PCI register offset: B3h
Register type: Read/Write, Read-Only, Read/Clear
Default value: 00h
Bit No. | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
Reset State | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
BIT | FIELD NAME | ACCESS | DESCRIPTION |
---|---|---|---|
7 | PROT_SEL(1) | rw | Protocol Select. This bit is used to select the serial bus address mode used. 0 – target Address and Byte Address are sent on the serial bus. 1 – Only the target address is sent on the serial bus. |
6 | RSVD | r | Reserved. Returns zero when read. |
5 | REQBUSY(1) | r | Requested Serial Bus Access Busy. This bit is set when a serial bus cycle is in progress. 0 – No serial bus cycle 1 – Serial bus cycle in progress |
4 | ROMBUSY(1) | r | Serial EEPROM Access Busy. This bit is set when the serial EEPROM circuitry in the TUSB73X0 is downloading register defaults from a serial EEPROM. 0 – No EEPROM activity 1 – EEPROM download in progress |
3 | SBDETECT(1) | rwu | Serial EEPROM Detected. This bit is automatically set when a serial EEPROM is detected by the TUSB73X0. The value of this bit is used to enable the serial bus interface and to control whether or not the EEPROM load takes place. Note that a serial EEPROM is only detected once following a PERST# or a GRST#. 0 – No EEPROM present, EEPROM load process does not happen 1 – EEPROM present, EEPROM load process takes place Note that even if a serial EERPOM is not detected following PERST# or a GRST#, software can still set this bit to enable the serial bus interface. In this situation, the EEPROM load process will not happen. |
2 | SBTEST(1) | rw | Serial Bus Test. This bit is used for internal test purposes. This bit controls the clock source for the serial interface clock. 0 – Serial bus clock at normal operating frequency ~ 100 kHz 1 – Serial bus clock frequency increased for test purposes |
1 | SB_ERR(1) | rc | Serial Bus Error. This bit is set when an error occurs during a software initiated serial bus cycle. 0 – No error 1 – Serial bus error |
0 | ROM_ERR(1) | rc | Serial EEPROM Load Error. This bit is set when an error occurs while downloading registers from a serial EEPROM. 0 – No Error 1 – EEPROM load error |