MAX11041_08 Datasheet, PDF (14/17 Pages) Maxim Integrated Products – Wired Remote Controllers

Wired Remote Controllers
VSENSE
1
2
3
4
5
6
7
8
9
10
11
12
TIME
VINT
TIME
t1
t2
t3
t4
t5
t6
1 _{SHDN TRANSITION FROM}
LOW TO HIGH.
READ
POINTER
0xFF
0xFF
0xFF
0xFF
0xFF
0xFF
0xFF
0xFF
WRITE
POINTER
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
2 _{OPEN CIRCUIT DETECTED}
AND ENTERED IN FIFO.
DURATION
TIMER STARTS.
READ
POINTER
0xFF
WRITE
POINTER
TIMER...
0xFF
0x00
0xFF
0x00
0xFF
0x00
0xFF
0x00
0xFF
0x00
0xFF
0x00
0xFF
0x00
3 _{JACK INSERTION DETECTED AND}
ENTERED IN FIFO. FINAL
DURATION TIME FROM 2
IS STORED. NEW DURATION TIME
READ FOR JACK DETECTION STARTS.
POINTER
0xFF
JD CODE
t1/32ms
WRITE
POINTER
TIMER...
0xFF
0x00
0xFF
0x00
0xFF
0x00
0xFF
0x00
0xFF
0x00
0xFF
0x00
4 _{JACK REMOVAL DETECTED (OPEN}
CIRCUIT) AND STORED IN FIFO.
FINAL DURATION TIME FROM 3
IS STORED. NEW DURATION TIME
READ FOR OPEN CIRCUIT STARTS.
POINTER
0xFF
JD CODE
0xFF
t1/32ms
t2/32ms
WRITE
POINTER
TIMER...
0xFF
0x00
0xFF
0x00
0xFF
0x00
0xFF
0x00
0xFF
0x00
5 JACK INSERTION DETECTED AND
ENTERED IN FIFO. FINAL
DURATION TIME FROM 4
IS STORED. NEW DURATION TIME
READ ^{FOR JACK DETECTION STARTS.}
POINTER
0xFF
t1/32ms
JD CODE
0xFF
t2/32ms
t3/32ms
WRITE
POINTER
JD CODE
TIMER...
0xFF
0x00
0xFF
0x00
0xFF
0x00
0xFF
0x00
6 μP READS UNTIL FIFO EMPTY
FLAG IS REACHED. FURTHER
READS RESULT IN JD CODE AND
CURRENT TIME DURATION
OF JD CODE BEING SENT.
READ
POINTER
0xFF
0xFF
0xFF
JD CODE
0xFF
0xFF
0xFF
0xFF
0x00
0x00
0x00
TIMER...
0x00
0x00
0x00
0x00
WRITE
POINTER
7 KEY PRESS DETECTED AND
ENTERED IN FIFO. FINAL TIME
DURATION FROM 6 IS STORED.
NEW DURATION TIME FOR
KEYPRESS STARTS.
8 μP READS UNTIL FIFO EMPTY
FLAG IS REACHED. FURTHER
READS RESULT IN KEY_ CODE
AND CURRENT TIME DURATION OF
KEY_ CODE BEING SENT.
READ
POINTER
0xFF
0xFF
0xFF
JD CODE
KEY_ CODE
0xFF
0xFF
0xFF
0x00
0x00
0x00
t4/32ms
TIMER...
0x00
0x00
0x00
WRITE
POINTER
READ
POINTER
0xFF
0xFF
0xFF
0xFF
KEY_ CODE
0xFF
0xFF
0xFF
0x00
0x00
0x00
0x00
TIMER...
0x00
0x00
0x00
WRITE
POINTER
9 KEY RELEASE DETECTED (JD
CODE) AND ENTERED IN FIFO.
FINAL DURATION TIME FROM 8 IS
STORED. NEW DURATION TIME
FOR JD CODE STARTS.
READ
POINTER
0xFF
0xFF
0xFF
0xFF
KEY_ CODE
JD CODE
0xFF
0xFF
0x00
0x00
0x00
0x00
t5/32ms
TIMER...
0x00
0x00
WRITE
POINTER
10 μP READS UNTIL FIFO EMPTY
FLAG IS REACHED. FURTHER
READS RESULT IN JD CODE AND
CURRENT TIME DURATION
OF JD CODE BEING SENT.
READ
POINTER
0xFF
0xFF
0xFF
0xFF
0xFF
JD CODE
0xFF
0xFF
0x00
0x00
0x00
0x00
0x00
TIMER...
0x00
0x00
WRITE
POINTER
11 JACK REMOVAL DETECTED (OPEN CIRCUIT)
AND STORED IN FIFO. FINAL
DURATION TIME FROM 10
IS STORED. NEW DURATION TIME
FOR OPEN CIRCUIT STARTS.
12 μP READS UNTIL FIFO EMPTY
FLAG IS REACHED. FURTHER
READS RESULT IN 0xFF AND
CURRENT TIME DURATION
BEING SENT.
READ
POINTER
0xFF
0xFF
0xFF
0xFF
0xFF
JD CODE
0xFF
0xFF
0x00
0xFF
0x00
0xFF
0x00
0xFF
0x00
0xFF
0x00
WRITE
POINTER
READ
0xFF
t6/32ms
POINTER
0xFF
TIMER...
0xFF
0x00
0xFF
0x00
0x00
0x00
0x00
0x00
0x00
TIMER...
0x00
*
WRITE
POINTER
DATA ENTERED
RESET DATA (POR)
*BOTH POINTERS WRAP AROUND TO THE TOP WHEN THEY GET TO THE END OF FIFO.
Figure 10. Power-Up, Jack Detect, and Keypress Example
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