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Rev. 1.10
80
March 02, 2020
Rev. 1.10
81
March 02, 2020
BS83A02L/BS83B04L
Ultra-Low Power Touch Key Flash MCU
BS83A02L/BS83B04L
Ultra-Low Power Touch Key Flash MCU
by application program.
Bit 2~1
TKMOD1~TKMOD0
: Touch key scan mode selection
00: Auto scan mode
01: Manual scan mode
10/11: Periodic auto scan mode
In the manual scan mode, the reference oscillator capacitor value should be properly
configured before the scan operation begins and the touch key module 0 16-bit C/F
counter value should be read after the scan operation finishes by application program.
In the auto scan mode, the data movement which is described above is implemented by
hardware. The individual reference oscillator capacitor value and 16-bit C/F counter
content for all scanned keys will be read from the TKM0KnROCH/TKM0KnROCL
and TKM0KnCNTH/TKM0KnCNTL registers. In the auto scan mode, the keys to be
scanned can be arranged in a specific sequence which is determined by the M0SK10
and M0SK00 bits in the TKM0C2 register. The scan operation will not be stopped
until all arranged keys are scanned.
In the periodic auto scan mode the touch key scan operation will be implemented
automatically on a periodic basis, which can be determined by the ASMP1~ASMP0
bits in the TKC2 register. Only at the end of the last scan operation in the WDT time-
out cycle, the 16-bit C/F counter content for all scanned keys will be written into the
TKM0KnCNTH/TKM0KnCNTL registers. In addition, when any key C/F counter
value is less than the lower threshold if M0KnTHS=0, or larger than the upper
threshold if M0KnTHS=1, the TKTH signal will be set high. The other actions in this
mode are the same as those in the auto scan mode except the above mentioned.
Bit 0
TKBUSY
: Touch key scan operation busy flag
0: Not busy – no scan operation is executed or scan operation is completed
1: Busy – scan operation is executing
This bit indicates whether the touch key scan operation is executing or not. It is set to 1
when the TKST bit is set high to start the scan operation for all touch key scan modes.
In the manual scan mode this bit is cleared to 0 automatically when the touch key time
slot counter overflows. In the auto scan mode this bit is cleared to 0 automatically
when the touch key scan operation is completed. In the periodic auto scan mode this
bit is cleared to 0 automatically when the last scan operation in the WDT time-out
cycle is completed, or when any key C/F counter value is less than the lower threshold
if M0KnTHS=0, or when the value is larger than the upper threshold if M0KnTHS=1.
• TKC1 Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
—
TK16S1
TK16S0
TKFS1
TKFS0
R/W
R/W
R/W
R/W
—
R/W
R/W
R/W
R/W
POR
0
0
0
—
0
0
1
1
Bit 7~5
D7~D5: Data bits for test only
These bits are used for test purpose only and must be kept as “000” for normal
operations.
Bit 4
Unimplemented, read as “0”
Bit 3~2
TK16S1~TK16S0
: Touch key function 16-bit counter clock source selection
00: f
SYS
01: f
SYS
/2
10: f
SYS
/4
11: f
SYS
/8
Bit 1~0
TKFS1~TKFS0
: Touch key oscillator and Reference oscillator frequency selection
00: 1MHz
01: 3MHz
10: 7MHz
11: 11MHz