TX4939XBG-400 Toshiba, TX4939XBG-400 Datasheet - Page 414

• Manufacturer Part Number: TX4939XBG-400
• Manufacturer: Toshiba

Specifications of TX4939XBG-400

• Cpu Core: TX49/H4 90nm
• Clock Mhz/max Mips: 400/520
• Inst./data Cache: 32KB (4 Way)/32KB (4 Way)
• Tlb: x
• 1cycle Mac: x
• Volts (v): 1.25/2.5/3.3
• Peripherals: DDR, NAND, ATA, ETHERNET, SECURITY, FPU, MMU, SPI, I2S, I2C, PCI, VIDEO, UART, TIMER, RTC
• Companion Chip: TC86C001FG
• Package: PGBA456

PCIC
16.4.29. PCI Bus Arbiter Current State Register (PBACSTATE)
This is a diagnostic register that is only valid when using the on-chip PCI Bus Arbiter.
Rev. 3.1 November 1, 2005
Default
Default
NAME
NAME
Bit
31:8
7
6
5:0
TYPE
TYPE
Mnemonic
FSM
CPAS
31
15
30
14
Field Name
Rsvd
Observe PCI
Arbiter State
Machine
Rsvd
Current PCI Bus
Arbiter State
29
13
RESERVED
Figure 16-40 PCI Bus Arbiter Current State Registe
Table 16-41 PCI Bus Arbiter Current State Registe
28
12
27
11
Description
Observe PCI Arbiter Finite State Machine (Default: 0)
Specifies which State Machine to observe.
1: Observe the Level 1 State Machine.
0: Observe the Level 2 State Machine.
Current PCI Bus Arbiter State (Default: 0x03)
Displays the State Machine that was selected by the FSM bit.
Please refer to Figure 16-13 for an explanation of Arbitration Flow.
When FSM =1:
0x00: Preparation state for transferring bus ownership to PCI Agent A.
0x01: State in which Grant A is provided to PCI Agent A when PCI Bus
ownership is being held elsewhere.
0x02: State in which Grant A is provided to PCI Agent A when PCI Bus
ownership is not being held elsewhere.
0x03: The agent that was provided Grant A exists in this state. If there is bus
ownership, the PCI Bus Arbiter transfers bus ownership to another agent.
0x04 – 0x07: Same as 0x00 – 0x03 but for PCI Agent B
0x08 – 0x0B: Same as 0x00 – 0x03 but for PCI Agent C
0x0C – 0x0F: Same as 0x00 – 0x03 but for PCI Agent D
0x10 : Preparation state for transferring bus ownership to PCI Agent Level 2.
0x11: State in which Grant Level 2 is provided to PCI Agent Level 2 when PCI
Bus ownership is being held elsewhere.
0x12: State in which Grant Level 2 is provided to PCI Agent Level 2 when PCI
Bus ownership is not being held elsewhere.
0x13: The agent that was provided Grant Level 2 exists in this state. If there is
bus ownership, the PCI Bus Arbiter transfers bus ownership to another agent.
When FSM=0, the FSM=1 description is replaced as follows: A→W, B→X,
C→Y, D→Z, Level 2→N/A.
26
10
25
9
16-50
RESERVED
24
8
FSM
R/W
23
7
0
22
6
0
21
5
20
Toshiba RISC Processor
4
19
3
CPAS
0x03
R
18
2
17
1
R/W
⎯
R/W
⎯
R
TX4939
16
0
16
16