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ST7LITEUS2, ST7LITEUS5
On-chip peripherals
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Counter register high (CNTRH)
Reset value: 0000 0000 (00h)
Counter register low (CNTRL)
This 12-bit register is read by software and cleared by hardware after a reset. The counter is
incremented continuously as soon as a counter clock is selected. To obtain the 12-bit value, software
should read the counter value in two consecutive read operations. As there is no latch, it is
recommended to read LSB first. In this case, CNTRH can be incremented between the two read
operations and to have an accurate result when f
timer
= f
CPU
, special care must be taken when
CNTRL values close to FFh are read.
When a counter overflow occurs, the counter restarts from the value specified in the ATR register.
Reset value: 0000 0000 (00h)
Auto reload register (ATRH)
Reset value: 0000 0000 (00h)
Table 29.
Counter clock selection
Counter clock selection
CK1
CK0
OFF
0
0
f
LTIMER
(1 ms timebase @ 8 MHz)
0
1
f
CPU
1
0
Reserved
1
1
15
8
0
0
0
0
CN11
CN10
CN9
CN8
Read only
7
0
CN7
CN6
CN5
CN4
CN3
CN2
CN1
CN0
Read only
Bits 15:12 Reserved, must be kept cleared.
Bits 11:0
CNTR[11:0]
Counter value
.
15
8
0
0
0
0
ATR11
ATR10
ATR9
ATR8
Read/Write
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