33972_09 Datasheet, PDF (18/32 Pages) Freescale Semiconductor, Inc – Multiple Switch Detection Interface with Suppressed Wake-up

FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
RESET
The reset command resets all registers to Power-ON
Reset (POR) state. Refer to Table 15, page 18, for POR
states or the paragraph entitled Power-ON Reset (POR) on
page 14 of this datasheet.
Table 14. Reset Command
Reset Command
Command Bits
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
0 1 1 1 1 1 1 1XXXXXXXXXXXXXXXX
SPI COMMAND SUMMARY
Table 15 below provides a comprehensive list of SPI
commands recognized by the 33972 and the reset state of
each register. Table 16 and Table 17 contain the serial
output (SO) data for input voltages greater or less than the
threshold level. Open switches are always indicated with a
logic [0], closed switches are indicated with logic [1].
Table 15. SPI Command Summary
Switch Status
Command
MSB
Command Bits
Setting Bits
LSBI
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
0 0 0 0 0 0 0 0XXXXXXXXXX X XXXXX
Settings Command
Bat = 1, Gnd = 0
(Default state = 1)
0 0 0 0 0 0 0 1 X X X X X X X X SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0
Wake-Up/Interrupt Bit 0 0 0 0 0 0 1 0 X X X X X X X X SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0
Wake-Up = 1
Non-Wake-Up = 0
(Default state = 1)
0 0 0 0 0 0 1 1 X X SG13 SG12 SG11 SG10 SG9 SG8 SG7 SG6 SG5 SG4 SG3 SG2 SG1 SG0
Metallic Command
Metallic = 1
Non-metallic = 0
(Default state = 1)
0 0 0 0 0 1 0 0 X X X X X X X X SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0
0 0 0 0 0 1 0 1 X X SG13 SG12 SG11 SG10 SG9 SG8 SG7 SG6 SG5 SG4 SG3 SG2 SG1 SG0
Analog Command
0
0
0
0
0
1
1
0
XX
X
X
X
X
X
X
X
16mA 2.0mA
0
0
0
0
0
0
0
Wetting Current Timer 0 0 0 0 0 1 1 1 X X X X X X X X SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0
Enable Command
Timer ON = 1
Timer OFF = 0
0 0 0 0 1 0 0 0 X X SG13 SG12 SG11 SG10 SG9 SG8 SG7 SG6 SG5 SG4 SG3 SG2 SG1 SG0
(Default state = 1)
Tri-State Command
Input Tri-State = 1
Input Active = 0
(Default state = 1)
0 0 0 0 1 0 0 1 X X X X X X X X SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0
0 0 0 0 1 0 1 0 X X SG13 SG12 SG11 SG10 SG9 SG8 SG7 SG6 SG5 SG4 SG3 SG2 SG1 SG0
Calibration Command
(Default state –
uncalibrated)
0 0 0 0 1 0 1 1XXXXXXXXXX X XXXXX
Sleep Command
int int int scan scan scan
(Refer to Sleep Mode ⁰
on page 19.)
0
0
0
1
1
0
0
XX
X
X
X
X
X
X
X
X
timer timer timer timer timer timer
Reset Command
0 1 1 1 1 1 1 1XXXXXXXXXX X XXXXX
SO Response Will
Always Send
them int
SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0 SG13 SG12 SG11 SG10 SG9 SG8 SG7 SG6 SG5 SG4 SG3 SG2 SG1 SG0
flg flg
33972
18
Analog Integrated Circuit Device Data
Freescale Semiconductor