Epson S1D13705 3 MC68EZ328 Chip Select Configuration, = configuration for MC68EZ328 support

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3.4.2 S1D13705 Hardware Configuration

The S1D13705 uses CNF3 through CNF0 and BS# to allow selection of the bus mode and other configuration data on the rising edge of RESET#. Refer to the S1D13705 Hardware Functional Specification, document number X27A-A-001-xx for details.

The tables below show those configuration settings important to the Generic #1 host bus interface.

Table 3-2: Summary of Power-On/Reset Options

S1D1370	value on this pin at the rising edge of RESET# is used to configure: (1/0)
5
	0	1
Pin Name
CNF0
	See Table 2-3: “Host Bus Interface Selection”
CNF1
CNF2
CNF3	Little Endian	Big Endian
	= configuration for MC68EZ328 support

Table 3-3: Host Bus Interface 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 MC68EZ328 using Generic #1 host bus interface

3.4.3 MC68EZ328 Chip Select Configuration

The S1D13705 requires a 128K byte address space for the display buffer and its internal registers. To accommodate this block size, it is preferable (but not required) to use one of the chip selects from groups A or B. Groups A and B can have a size range of 128K bytes to 16M bytes and groups C and D have a size range of 32K bytes to 16M bytes. Therefore, any chip select other than CSA0 would be suitable for the S1D13705 interface.

In the example interface, chip select CSB0 is used to control the S1D13705. A 128K byte address space is used with the S1D13705 control registers mapped into the top 32 bytes of the 128K byte block and the 80K bytes of display buffer mapped to the starting address of the block. The chip select should have its RO (Read Only) bit set to 0, its BSW (Bus Data

S1D13705	Interfacing to the Motorola ‘Dragonball’ Family of Microprocessors
X27A-G-007-04	Issue Date: 01/02/13