Embedded Pentium® Processor-Based POS Terminal Sample Design

Table 11. Multifunction (MFUNC[6:0]) Board Connections

6.7ISA PCI Expansion Cards

There are two PCI expansion slots on this sample design, allowing for add-in card peripherals to enhance any design. There is also one ISA expansion slot in the design. With the variety of peripherals in this design that would ordinarily be implemented through an add-in card, two extra PCI slots and one extra ISA slot allows for functionality that has not been added.

6.7.1Design Note

•ISA Bus/Expansion Slots

As discussed on the Intel®430TX PCIset Design Guide (order number 290613), pull-up and pull-down resistors should be placed as follows:

—10 K Ω pull-ups on SD[15:0] and SA[19:0].

—1 K Ω pull-up on IOCHRDY and REFRESH#.

—10 K Ω pull-up on IRQx (10 KΩ pull-up on IRQ8, MEMR#, MEMW#, IOR#, IOW#, LA[23:17], SMEMR#, SMEMW#, SBHE#, and BALE.

—330 Ω on ZEROWS#, MASTER#, MEMCS16#, and IOCS16#.

—4.7 K Ω on IOCHK#.

—5.6 K Ω pull-down resistors on DRQx.

•PCI Bus/Expansion Slots

Per the Intel®430TX PCIset Design Guide, place pull-up signal resistors on the following:

—2.7 K Ω pull-up resistors to 5 V on PIRQ[D:A]#, SDONE, SBO#, FRAME#, TRDY#, STOP#, IRDY#, DEVSEL#, PLOCK#, PERR#, SERR#, REQ64# and ACK64# and PAR

—10 K Ω pull-ups to 3.3 V on GNT[3:0]#, PHLD# and PHLDA#.

There are two PCI expansion slots on the board. Slot 0 is PCI device #17, Slot 1 is PCI device #18 (IDSEL connected to AD28 and AD29 through a 220 Ω resistor respectively). Each slot is connected to PCI bus master arbitration pins REQ# and GNT#. Slot 0 is connected to GNT0# and REQ0#, and Slot 1 is connected to GNT1# and REQ1#.

Note: For layout considerations when placing series resistors, refer to the Intel®430TX PCIset Design Guide.