TI380PCIA Datasheet, PDF (21/40 Pages) Texas Instruments – PCI BUS INTERFACE FOR THE TI380 COMMPROCESSORS

TI380PCIA
PCI BUS INTERFACE FOR THE TI380 COMMPROCESSORS™
SPWS035 – JUNE 1997
device identification
The TI380PCIA contains the device identification information in its configuration space as shown in Table 5.
Table 5. Device Identification
REGISTER
Vendor ID
Device ID
HEX VALUE
104Ch†
0508h†
Revision ID
01
Class code
028000
Header type
00
† _{These values are defaults and can be overwritten by the}
contents of the optional EEPROM.
command register—configuration space DWORD address (0x04)
Figure 8 shows the command register layout.
15
10 9 8 7 6 5 4 3 2 1 0
Reserved
0
0
0
Fast Back-to-Back Enable
SERR Enable
Wait-Cycle Control
Parity-Error Response
VGA Palette Snoop
Memory Write-and-Invalidate Enable
Special Cycles
Bus Master
Memory Space
I / O Space
Figure 8. Command Register Layout
The command register provides coarse control over the TI380PCIA’s ability to generate and to respond to PCI
cycles. When 0 is written to this register, the device is logically disconnected from the PCI bus for all accesses
except configuration accesses.
The command register is set to 0 at power up and after hardware reset.
Bit 00: I/O space. Controls the TI380PCIA’s response to I / O space accesses. A value of 0 disables the
TI380PCIA’s response. A value of 1 allows the TI380PCIA to respond to I / O space accesses.
Bit 01: Memory space. Controls the TI380PCIA’s response to memory space accesses. A value of 0 disables
the TI380PCIA’s response. A value of 1 allows the TI380PCIA to respond to memory space accesses.
Bit 02: Bus master. Controls the TI380PCIA’s ability to act as a master on the PCI bus. A value of 0 disables
TI380PCIA from generating PCI accesses. A value of 1 allows the TI380PCIA to behave as a bus master. If the
automatic software-reset bit in the TI380PCIA interface control register (0x54) is set to a one, then the action
of clearing the bus master bit of the TI380PCIA command register from one to zero also resets the TI380PCIA.
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