Intel 80C196NU ユーザーズマニュアル
8XC196NP, 80C196NU USER’S MANUAL
13-12
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.
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.
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.