Owner's manual
DS3131 
136 of 174 
Register Name:   PRCC1 
Register Description:  PCI Revision ID/Class Code Register 1 
Register Address:  0x108h 
LSB 
Revision ID (Read Only/Set to 00h) 
Class Code (Read Only/Set to 00h) 
Class Code (Read Only/Set to 80h) 
MSB 
Class Code (Read Only/Set to 06h) 
Bits 0 to 7/Revision ID. These read-only bits identify the specific device revision, selected by Dallas 
Semiconductor. 
Bits 8 to 15/Class Code Interface. These read-only bits identify the subclass interface value for the device and 
are fixed at 00h. See Appendix D of PCI Local Bus Specification Revision 2.1 for details. 
Bits 16 to 23/Class Code Subclass. These read-only bits identify the subclass value for the device and are fixed at 
80h, indicating “Other Bridge Device.” See Appendix D of PCI Local Bus Specification Revision 2.1 for details. 
Bits 24 to 31/Class Code Base Class. These read-only bits identify the base class value for the device and are 
fixed at 06h, which indicate “Bridge Devices.” See Appendix D of PCI Local Bus Specification Revision 2.1 for 
details. 
Register Name:  PLTH1 
Register Description:  PCI Latency Timer/Header Type Register 1 
Register Address:  0x10Ch 
LSB 
Cache Line Size (Read Only/Set to 00h) 
Latency Timer (Read Only/Set to 00h) 
Header Type (Read Only/Set to 80h) 
MSB 
BIST (Read Only/Set to 00h) 
Bits 0 to 7/Cache Line Size. These read-only bits are forced to 0. 
Bits 8 to 15/Latency Timer. These read-only bits are forced to 0 by the device since the device cannot act as a 
bus master. 
Bits 16 to 23/Header Type. These read-only bits are forced to 80h, which indicate a multifunction device. 
Bits 24 to 31/Built-In Self-Test (BIST). These read-only bits are forced to 0. 










