USB 2.0
Datasheet
4.4.7Bus Reset Sequence
The SMBus Slave Interface resets and returns to the idle state upon a START field followed immediately by a STOP field.
4.4.8SMBus Alert Response Address
The SMBALERT# signal is not supported by the Hub.
4.4.8.1Undefined Registers
The registers shown in Table 4.2 are the defined registers in the Hub. Reads to undefined registers return 00h. Writes to undefined registers have no effect and do not return an error.
4.4.8.2Reserved Registers
Unless otherwise instructed, only a ‘0’ may be written to all reserved registers or bits.
4.5Default Configuration Option:
The SMSC Hub can be configured via its internal default configuration. (please see Section 4.3.1, "Internal Register Set (Common to EEPROM and SMBus)" for specific details on how to enable default configuration.)
Please refer to Table 4.2 for the internal default values that are loaded when this option is selected.
4.6Default Strapping Options:
The USB2514 can be configured via a combination of internal default values and pin strap options. Please see Table 3.1 and Table 3.2 for specific details on how to enable the
The strapping option pins only cover a limited
The Amber and Green LED pins are sampled after RESET_N negation, and the logic values are used to configure the hub if the internal default configuration mode is selected. The implementation shown below (see Figure 4.3) shows a recommended passive scheme. When a pin is configured with a “Strap High” configuration, the LED functions with active low signalling, and the PAD will “sink” the current from the external supply. When a pin is configured with a “Strap Low” configuration, the LED functions with active high signalling, and the PAD will “source” the current to the external LED.
SMSC USB2514 | 37 | Revision 1.98 |
| DATASHEET |
|