EM6517 ETC, EM6517 Datasheet - Page 42

• Manufacturer Part Number: EM6517
• Description: 4 BIT MICROCONTROLLER
• Manufacturer: ETC

15 Strobe Output
The Strobe output is used to indicate either the EM6517-1 reset condition, a write operation on port B (WritePB)
or the sleep mode. The selection is done in register RegLcdCntl1. Per default, the reset condition is output on
the Strobe terminal.
For a port B write operation the strobe signal goes high for half a system clock period. Data can be latched on
the falling edge of the strobe signal. This function is used to indicate when data on port B output terminals is
changing.
The reset signal on the Strobe output is a copy of the internal CPU reset signal. The Strobe pin remains active
high as long as the CPU gets the reset.
Both the reset condition and the port B write operation can be output simultaneously on the Strobe pin.
The strobe output select latches are reset by initial power on reset only.
Table 13.1.1. Strobe Output Selection
15.1 Strobe register
Table 15.1.1 register OPTPCandStr
© EM Microelectronic-Marin SA, 09/99, Rev. A/277
42
StrobeOutSel1
Default : System reset on STROBE output
0
0
1
1
Bit
3
2
1
0
StrobeOutSel0
StrobeOutSel1
StrobeOutSel0
NchOpDPC
NoPdPC
Name
0
1
0
1
FOR ENGINEERING ONLY
System Reset
Power on
Terminal
WritePB
WritePB
System
Output
Strobe
Reset
Sleep
value
and
0
0
0
0
R/W
R/W
R/W
R/W
R/W
Figure 31 . Strobe Output
StrobeOutSel0
Reset
Reset, WritePB
WritePB
StrobeOutSel1
Sleep
N-Channel Open Drain on PortC
Strobe output selection
Strobe output selection
no pull-down on PortC
Description
0
1
2
3
0
1
EM6517
Terminal
Strobe