pdi1394p25 NXP Semiconductors, pdi1394p25 Datasheet - Page 15

• Manufacturer Part Number: pdi1394p25
• Description: 1-port 400 Mbps Physical Layer Interface
• Manufacturer: NXP Semiconductors

Philips Semiconductors
16.0 INTERNAL REGISTER CONFIGURATION
There are 16 accessible internal registers in the PDI1394P25. The
configuration of the registers at addresses 0 through 7 (the base
registers) is fixed, while the configuration of the registers at
addresses 8h through Fh (the paged registers) is dependent upon
which one of eight pages, numbered 0h through 7h, is currently
selected. The selected page is set in base register 7h.
Table 1. Base Register Configuration
Table 2. Base Register Field Descriptions
2001 Sep 06
Physical ID
R
CPS
RHB
IBR
Gap_Count
Extended
Num_Ports
PHY_Speed
Delay
ADDRESS
ADDRESS
1-port 400 Mbps physical layer interface
FIELD
0000
0001
0010
0100
0101
0011
0110
0111
SIZE
RPIE
RHB
LCtrl
6
1
1
1
1
6
3
4
3
4
0
Rd/Wr
Rd/Wr
Rd/Wr
TYPE
PHY_Speed (010b)
Rd
Rd
Rd
Rd
Rd
Rd
Rd
Extended (111b)
Page_Select
ISBR
IBR
This field contains the physical address ID of this node determined during self-ID. The physical-ID is
invalid after a bus reset until self-ID has completed as indicated by an unsolicited register-0 status
transfer.
Root. This bit indicates that this node is the root node. The R bit is reset to 0 by bus reset, and is set to
1 during tree-ID if this node becomes root.
Cable-power-status. This bit indicates the state of the CPS input terminal. The CPS terminal is normally
tied to serial bus cable power through a 390 k resistor. A 0 in this bit indicates that the cable power
voltage has dropped below its threshold for ensured reliable operation.
Root-holdoff bit. This bit instructs the PHY to attempt to become root after the next bus reset. The RHB
bit is reset to 0 by a hardware reset, and is unaffected by a bus reset.
Initiate bus reset. This bit instructs the PHY to initiate a long (166 s) bus reset at the next opportunity.
Any receive or transmit operation in progress when this bit is set will complete before the bus reset is
initiated. The IBR bit is reset to 0 after a hardware reset or a bus reset.
Arbitration gap count. This value is used to set the subaction (fair) gap, arb-reset gap, and arb-delay
times. The gap count can be set either by a write to the register, or by reception or transmission of a
PHY_CONFIG packet. The gap count is reset to 3Fh by hardware reset or after two consecutive bus
resets without an intervening write to the gap count register (either by a write to the PHY register or by
a PHY_CONFIG packet).
Extended register definition. For the PDI1394P25, this field is 111b, indicating that the extended register
set is implemented.
Number of ports. This field indicates the number of ports implemented in the PHY. For the PDI1394P25
this field is 1.
PHY speed capability. For the PDI1394P25, this field is 010b, indicating S400 speed capability.
This field is not applicable for the single-port P25 and should always read as 0001 binary.
C
1
CTOI
2
Physical ID
Jitter (000)
Rsvd
Rsvd
CPSI
Rsvd
15
3
BIT POSITION
Reserved
register field definitions are unaffected by the selected page number.
the following register configuration tables) is read as 0, but is subject
The configuration of the base registers is shown in Table 1, and
corresponding field descriptions are given in Table 2. The base
A reserved register or register field (marked as Reserved or Rsvd in
to future usage. All registers in address pages 2 through 6 are
reserved.
DESCRIPTION
STOI
4
Gap_Count
Num_Ports (0001b)
PEI
5
Delay (0001b)
Port Select
Pwr_Class
EAA
PDI1394P25
R
6
Preliminary data
EMC
CPS
7