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Epson Research and Development
Vancouver Design Center
S1D13704
Interfacing to the Motorola MPC821 Microprocessor
X26A-G-010-03
Issue Date: 01/02/12
4.3 S1D13704 Hardware Configuration
The S1D13704 uses CNF4 through CNF0 and BS# to allow selection of the bus mode and
other configuration data on the rising edge of RESET#. Refer to the S1D13704 Hardware
Functional Specification, document number X26A-A-001-xx for details.
The tables below show only those configuration settings important to the MPC821
interface. The settings are very similar to the ISA bus with the following exceptions:
• the WAIT# signal is active high rather than active low.
• the Power PC is big endian rather than little endian.
Table 4-2: Configuration Settings
Signal
Low
High
CNF0
See “Host Bus Selection” table below
See “Host Bus Selection” table below
CNF1
CNF2
CNF3
Little Endian
Big Endian
CNF4
Active low LCDPWR signal
Active high LCDPWR signal
= configuration for MPC821 host bus interface
Table 4-3: Host Bus Selection
CNF2
CNF1
CNF0
BS#
Host Bus Interface
0
0
0
X
SH-4 interface
0
0
1
X
SH-3 interface
0
1
0
X
reserved
0
1
1
X
MC68K #1, 16-bit
1
0
0
X
reserved
1
0
1
X
MC68K #2, 16-bit
1
1
0
0
reserved
1
1
0
1
reserved
1
1
1
0
Generic #1, 16-bit
1
1
1
1
Generic #2, 16-bit
= configuration for MPC821 host bus interface
*