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Scanning the reset pin, Figure 88, Figure 88 t – Rainbow Electronics ATmega162V User Manual

Page 209: Atmega162/v, Data b u s, See boundary-scan description for details

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209

ATmega162/V

2513E–AVR–09/03

Figure 88. General Port Pin Schematic Diagram

Scanning the RESET pin

The RESET pin accepts 5V active low logic for standard reset operation, and 12V active
high logic for high voltage parallel programming. An observe-only cell as shown in Fig-
ure 89
is inserted both for the 5V reset signal; RSTT, and the 12V reset signal; RSTHV.

Figure 89. Observe-only Cell

CLK

RPx

RRx

WRx

RDx

WDx

PUD

SYNCHRONIZER

WDx:

WRITE DDRx

WRx:

WRITE PORTx

RRx:

READ PORTx REGISTER

RPx:

READ PORTx PIN

PUD:

PULLUP DISABLE

CLK :

I/O CLOCK

RDx:

READ DDRx

D

L

Q

Q

RESET

RESET

Q

Q

D

Q

Q

D

CLR

PORTxn

Q

Q

D

CLR

DDxn

PINxn

D

ATA

B

U

S

SLEEP

SLEEP:

SLEEP CONTROL

Pxn

I/O

I/O

See Boundary-Scan Description

for Details!

PUExn

OCxn

ODxn

IDxn

PUExn:

PULLUP ENABLE for pin Pxn

OCxn:

OUTPUT CONTROL for pin Pxn

ODxn:

OUTPUT DATA to pin Pxn

IDxn:

INPUT DATA from pin Pxn

0

1

D

Q

From

Previous

Cell

ClockDR

ShiftDR

To

Next

Cell

From System Pin

To System Logic

FF1