em78p131a ELAN Microelectronics Corp, em78p131a Datasheet - Page 25

• Manufacturer Part Number: em78p131a
• Description: 8-bit Microcontroller With Otp Rom
• Manufacturer: ELAN Microelectronics Corp

Product Specification (V1.2) 09.16.2009
(This specification is subject to change without further notice)
5.5.3 Status of RST, T, and P of the Status Register
A Reset condition is initiated by the following events
1) A power-on condition
2) A high-low-high pulse on /RESET pin
3) Watchdog timer time-out
The values of T and P listed in the table below are used to check how the processor
wakes up.
Table 2 Values of RST, T, and P after a Reset
The following table shows the events that may affect the status of T and P.
Table 3 Status of T and P Being Affected by Events
Power on
WDTC instruction
WDT time-out
SLEP instruction
Wake-up on pin change during Sleep mode
Power on
/RESET during Operating mode
/RESET wake-up during Sleep mode
WDT during Operating mode
WDT wake-up during Sleep mode
Wake-up on pin change during Sleep mode
Reset Type
Event
Figure 5-9 Controller Reset Block Diagram
RST
RST
8-Bit Microcontroller with OTP ROM
*
*
0
0
0
0
0
1
0
0
1
P
P
*
*
P: Previous status before reset
P: Previous status before reset
*
T
T
1
1
0
0
1
1
1
0
1
1
P
EM78P131A
*
*
*
P
P
1
0
0
0
1
1
0
0
P
P
P
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