DSP 104-plus, Reference Manual

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not 5V tolerant. This means that the TP400 cannot be used with PC/104-Plus or PCI
boards which have 5V signal levels. It will operate with 3.3V boards and with boards
which support either 3.3V or 5V operation. The TCVIDEO video capture board from
DSP Design can be used with the TP400. The TP400’s VI/O power supply pins are
configured to be at 3.3V.
Most of the PCI bus signals are bussed to all PCI boards in the system. Some signals
however are unique to each board. These are the IDSEL, clock, bus request and
grant pins. The interrupt pins also receive special treatment.
Each board receives a different address pin routed to its IDSEL pin. This allows each
PCI board to be allocated an individual "PCI Device" number. The IDSEL pin is used
during the configuration of each PCI Device. The PC/104-Plus spec states that the
four IDSEL signals should be connected to AD20-23.
There is a separate 33.3MHz clock for each board.
The bus request/bus grant signals are also routed to each board separately. Note
however that the TP400 only supports bus request/bus grant signals to the first two
PCI expansion boards.
The interrupt pins are "rotated" one position with every board. The means that if four
PCI boards are each asserting a single interrupt request (on their INTA# pin), the PCI
bridge (in the CS5530A chip) receives four different interrupt requests, one on each
of its four INTx# pins.
Table 8 describes the allocation of these point-to-point signals within a TP400
system. This table also notes the allocation of the IDSEL signals to the PCI functions
within the CS5530A chip. (The CS5530A incorporates two PCI functions - the USB
Controller and the "Chip set registers", which include the PCI to ISA bus bridge,
audio, video, IDE and power management functions).
PC/104+
MODULE
SLOT SWITCH
POSIT-
ION IDSEL
ADDR. PCI
DEVICE CLK PIN REQ/
GNT
PAIR 5530A
INTA# 5530A
INTB# 5530A
INTC# 5530A
INTD#
1 0 or 4 AD20 Ah CLK0 0 INTA# INTB# INTC# INTD#
2 1 or 5 AD21 Bh CLK1 1 INTB# INTC# INTD# INTA#
3 2 or 6 AD22 Ch CLK2 - INTC# INTD# INTA# INTB#
4 3 or 7 AD23 Dh CLK3 - INTD# INTA# INTB# INTC#
5 - AD24 Eh - 1 INTA# - - -
CS5530A Chip
Set Registers - AD28 12h - - - - - -
CS5530A USB
Controller - AD29 13h - - INTA# - - -
TABLE 8 - PCI BUS RESOURCE ALLOCATIONS
The on-board Ethernet chip is normally configured as slot 4, although it could be
configured as a slot 5 device (see Appendix B for configuration options). The slot 5
entry in the above table is for the Ethernet chip when it is configured as slot 5.
For a full description of the PCI bus, see the PCI bus specification (www.pcisig.com).
The PC/104-Plus specification (version 1.1) is available on DSP Design's web site
(www.dspdesign.com).