Chapter 8: PCI/G-Bus Bridge
TX7901 User’s Manual (Rev. 6.30T – Nov, 2001)
8-2
•
Implements up to eight posted write transactions for PCI memory write commands.
•
Implements delayed read transactions for all PCI Master I/O and memory read
commands – only one transaction at a time.
•
Implements “conditional” delayed read transactions for all GBUS master configuration,
I/O, and memory read commands to PCI – only one transaction at a time.
•
Implements posted write transactions for all G-Bus master configuration, I/O, and
memory write commands to PCI – up to eight transactions at a time.
•
Implements mapping functions between G-Bus and PCI addresses:
‒
32-bit G-Bus to 32-bit PCI I/O mapping
‒
No support for the ISA-aware mode
•
On-chip PCI arbiter for up to five PCI master devices
‒
Allows use of external arbiter
The PGB is based on a 66MHz PCI core. The bridge logic interfaces to the PCI core on one
side and to the G-Bus on the other side as shown in Figure 8-1.
Figure 8-1 Top level Block Diagram
PCI BUS
PGB Core
PCI Arbiter
PCI Core
66 MHz
PCI to G-Bus
BRIDGE
G-Bus Interface
Master
G-Bus
G-Bus Interface
Slave
REQ#
GNT#
Summary of Contents for TMPR7901
Page 1: ...TX System RISC TX79 Family TMPR7901 Symmetric 2 way superscalar 64 bit CPU ...
Page 14: ...Handling Precautions ...
Page 15: ......
Page 17: ...1 Using Toshiba Semiconductors Safely 1 2 ...
Page 41: ...4 Precautions and Usage Considerations 4 2 ...
Page 42: ...TX7901 User s Manual Rev 6 30T November 2001 DOCUMENT NUMBER M 99 00004 07 ...
Page 43: ......
Page 259: ...Chapter 13 Removed TX7901 User s Manual Rev 6 30T Nov 2001 13 1 13 Removed ...
Page 260: ...Chapter 13 Removed TX7901 User s Manual Rev 6 30T Nov 2001 13 2 ...