Intel Microcontroller, 80C196NU, 8XC196NP manual Example of a Chip-select Setup

8XC196NP, 80C196NU USER’S MANUAL

Use the following sequence to initialize the chip-select registers after reset:

1.Initialize chip-select output 0:

1.1.Clear ADDRMSK0.

1.2.Write to ADDRCOM0 to establish the desired base address.

1.3.Write to ADDRMSK0 to establish the desired address range.

1.4.Write the desired bus-parameter values to BUSCON0.

2.While executing in the address range defined in step 1 for chip-select output 0, use the following sequence to initialize chip-select outputs 1–5. Begin with x = 1.

2.1.Load ADDRMSKx with 0FFFH.

2.2.Write to ADDRCOMx to establish the desired base address.

2.3.Write to ADDRMSKx to establish the desired address range.

2.4.Write the desired bus-parameter values to BUSCONx.

2.5.Repeat steps 2.1–2.4 for x = 2–5.

13.3.5 Example of a Chip-select Setup

This section shows an example of setting up the chip-select unit and provides details of the chip- select output calculation. This example shows how to set up the chip-select registers for the sys- tem shown in Figure 13-5. For each address range, the BUSCONx register (see Figure 13-4) spec- ifies the address/data multiplexing (bit 7), the bus width (bit 6), and the number of wait states (bits 1, 0). Table 13-8 lists the characteristics of the three chip-select outputs and the corresponding contents of BUSCONx.

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