DEM16216SYH-LY Datasheet, PDF (13/22 Pages) List of Unclassifed Manufacturers – DEM16216SYH-LY

DEM 16216 SYH-LY
Product Specification
10. INTERFACE WITH MPU IN BUS MODE
1) Interface with 8-bit MPU
When interfacing data length are 8-bit, transfer is performed all at once through 8-ports, from DB0 to DB7.
An example of the timing sequence is shown below.
RS
R/W
E
internal Singnal
DB7
Data
internal Operation
Busy
Busy
No
Busy
instruction
Busy Flag
check
Busy Flag
check
Busy Flag
check
Data
instruction
Figure 6.0 Example of 8-bit bus mode timing diagram
2) Interface with 4-bit MPU
When interfacing data length are 4-bit, only 4 ports, from DB4 to DB7, are used as data bus.
At first, higher 4-bit (in case of 8-bit bus mode, the contents of DB4 to DB7) are transferred, and then the lower 4-bit
(in case of 8-bit bus mode, the contents of DB0 to DB3) are transferred. So transfer is performed in two parts. Busy
flag outputs”1”after the second transfer are ended.
Example of timing sequence is shown below.
RS
R/W
E
internal Singnal
DB7
instruction
internal Operation
Busy
No
Busy
Busy Flag check
Busy Flag Check
instruction
Figure 7.0 Example of 4-bit bus mode timing
diagram
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