OX16PCI952-TQAG OXFORD [Oxford Semiconductor], OX16PCI952-TQAG Datasheet - Page 14

• Manufacturer Part Number: OX16PCI952-TQAG
• Description: Integrated High Performance Dual UARTs, Parallel Port and 5.0v PCI interface
• Manufacturer: OXFORD [Oxford Semiconductor]

5
The OX16PCI952 is a multi-function, target-only PCI
device, compliant with the PCI Local Bus Specification,
Revision 2.2 and PCI Power Management Specification,
Revision 1.0.
The OX16PCI952 affords maximum configuration flexibility
by treating the internal UARTs and the parallel port as
separate logical functions (function 0 and function 1,
respectively). Each function has its own PCI configuration
space and is therefore recognised and configured by the
PCI BIOS separately (each function operates as though it
were a separate device). The device can also be
configured to operate as a single function device by making
available only the internal UARTs. This is controlled by the
Mode pin, as shown in Table 3.
The OX16PCI952 is configured by system start-up
software during the bootstrap process that follows bus
reset. The system scans the PCI bus and reads the vendor
and device identification codes from any devices/functions
it finds and the resources being requested. It then loads the
device-driver software according to this information and
configures the I/O, memory and interrupt resources. Device
drivers can then access the functions at the assigned
DS-0028 Jul 05
OXFORD SEMICONDUCTOR LTD.
C
Mode
ONFIGURATION
0
1
Configuration
Dual Function Device Mode.
Function 0 is the Dual UART. Function 1 is the parallel port
Single Function Device Mode.
Function 0 is the Dual UART. Function 1 (Parallel Port) is not available.
& O
PERATION
Table 3: Mode configuration
External-Free Release
addresses in the usual fashion, with the improved data
throughput provided by PCI.
A set of local configuration registers have been provided
that can be used to control the device’s characteristics
(such as interrupt handling) and report internal functional
status. This is on top of the UART and the Parallel Port
registers, and the registers contained in each of the 2
function’s PCI configuration Space. These local registers
are common to both functions and can be set up by the
device drivers of function 0 and function 1, or from the
optional EEPROM.
The EEPROM can also be used to redefine the reset
values of most register areas to tailor the device to the end
users requirements if the default values do not meet the
specific requirements of the manufacturer, such as the
identification registers. As an additional enhancement, the
EEPROM can be used to pre-program each UART and the
Parallel Port, allowing pre-configuration, without requiring
device driver changes. This, for example, does allow the
enhanced features of the integrated UARTs to be in place
prior to handover to any generic device drivers. A similar
arrangement is available for the parallel port.
OX16PCI952
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