Mc68340 Mpu Interface; Mc68340 Setup - Epson SED1352 Technical Manual

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2 MC68340 MPU INTERFACE

The following sections provide the necessary settings and equations to complete the interface between the SED1352 and
the MC68340 microcontroller.
MC68340
CS3
SIZ0
A0-A19
D0-D15
DSACK1
AS
R/W
RESET

2.1 MC68340 Setup

For the purpose of this example, the following conditions apply:
The internal chip select signal CS3 of the MC68340, along with external DSACK1 response, is employed to access the
SED1352. Direct mapping of the I/O with starting address at 00000000h, and 128Kbytes of display memory with starting
address 00020000h are also used.
1. CS3 with 256kbyte block size - starting address at 00000000h and ending address at 0003FFFFh
2. External DSACK1 response - 16-bit port
3. Don't care Function Codes and with CPU space access
4. Both read and write accesses are allowed
Settings for the Address Mask register and Base Address register for the above conditions are:
058h - 05Bh
05Ch - 05Fh
SED1352
X16-AN-004-06
A0
A10-A17
Figure 1: MC68340 MPU Interface Block Diagram
= 0003FFFFh Address Mask register
= 000000F5h Base Address register
PAL
V
CC
V
CC
4.7kΩ
Epson Research and Development
Vancouver Design Center
SED1352
MEMCS#
IOCS#
VD0-VD3
BHE#
VD13
AB0-AB19
DB0-DB15
MEMR#
MEMW#
READY
IOR#
IOW#
RESET
MC68340 Interface Considerations
Issue Date: 98/10/08
V
CC
10kΩ