Rainbow Electronics DS3131 - Manual (Page 133)

DS3131
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Register Name:
PVID1
Register Description:
PCI Vendor ID/Device ID Register 1
Register Address: 0x100h
LSB
Vendor ID (Read Only/Set to EAh)
Vendor ID (Read Only/Set to 13h)
Device ID (Read Only/Set to 31h)
MSB
Device ID (Read Only/Set to 31h)
Bits 0 to 15/Vendor ID. These read-only bits identify Dallas Semiconductor as the manufacturer of the device.
The vendor ID was assigned by the PCI Special Interest Group and is fixed at 13EAh.
Bits 16 to 31/Device ID. These read-only bits identify the DS3131 as the device being used. The device ID was
assigned by Dallas Semiconductor and is fixed at 3131h.
Register Name:
PCMD1
Register Description:
PCI Command/Status Register 1
Register Address: 0x104h
LSB
STEPC PARC VGA MWEN SCC MASC MSC IOC
Reserved (Read Only/Set to All Zeros) FBBEN PSEC
FBBCT UDF 66 MHz Reserved (Read Only/Set to All Zeros)
MSB
PPE PSE MABT TABTM TABT DTS1 DTS0 PARR
Note: Read-only bits in the PCMD1 register are underlined; all other bits are read-write.
The lower word (bits 0 to 15) of the PCMD1 register is the command portion and is used for the PCI bus control.
When all bits in the lower word are set to 0, the device is logically disconnected from the bus for all accesses,
except for accesses to the configuration registers. The upper word (bits 16 to 31) is the status portion and is used
for status information. Reads to the status portion behave normally but writes are unique in that bits can be reset
(i.e. forced to 0) but not set (i.e. forced to 1). A bit in the status portion is reset when 1 is written to that bit
position. Bit positions that have 0 written to them do not reset.