Rev. 1.00
54
March 24, 2020
Rev. 1.00
55
March 24, 2020
BS83A04C
4-Key Enhanced Touch I/O Flash MCU
BS83A04C
4-Key Enhanced Touch I/O Flash MCU
• Reading Data from the Counter Registers and CCRA
♦
Step 1. Read data from the High Byte CTMDH, CTMAH
– Here data is read directly from the High Byte registers and simultaneously data is latched
from the Low Byte register into the 8-bit buffer.
♦
Step 2. Read data from the Low Byte CTMDL, CTMAL
–
This step reads data from the 8-bit buffer.
Compact Type TM – CTM
Although the simplest form of the three TM types, the Compact TM type still contains three
operating modes, which are Compare Match Output, Timer/Event Counter and PWM Output modes.
The Compact TM can also be controlled with an external input pin and can drive two external output
pins.
f
SYS
f
SYS
/4
f
H
/64
f
H
/16
f
SUB
CTCK
000
001
010
011
100
101
110
111
CTCK2~CTCK0
10-bit Count-up Counter
3-bit Comparator P
CCRP
b7~b9
b0~b9
10-bit Comparator A
CTON
CTPAU
Comparator A Match
Comparator P Match
Counter Clear
0
1
Output
Control
Polarity
Control
Pin
Control
CTOC
CTM1, CTM0
CTIO1, CTIO0
CTMAF Interrupt
CTMPF Interrupt
CTPOL
CCRA
CTCCLR
PASn
f
SUB
CTPB
CTP
Note: CTPB is the inverted output of CTP.
Compact Type TM Block Diagram
Compact TM Operation
At its core is a 10-bit count-up counter which is driven by a user selectable internal or external clock
source. There are also two internal comparators with the names, Comparator A and Comparator
P. These comparators will compare the value in the counter with CCRP and CCRA registers. The
CCRP is three bits wide whose value is compared with the highest three bits in the counter while the
CCRA is the ten bits and therefore compares with all counter bits.
The only way of changing the value of the 10-bit counter using the application program, is to
clear the counter by changing the CTON bit from low to high. The counter will also be cleared
automatically by a counter overflow or a compare match with one of its associated comparators.
When these conditions occur, a CTM interrupt signal will also usually be generated. The Compact
Type TM can operate in a number of different operational modes, can be driven by different clock
sources including an input pin and can also control two output pins. All operating setup conditions
are selected using relevant internal registers.
Compact Type TM Register Description
Overall operation of each Compact TM is controlled using several registers. A read only register
pair exists to store the internal counter 10-bit value, while a read/write register pair exists to store
the internal 10-bit CCRA value. The remaining two registers are control registers which setup the
different operating and control modes as well as the three CCRP bits.
