XE8000EV110 Semtech, XE8000EV110 Datasheet - Page 178

• Manufacturer Part Number: XE8000EV110
• Description: EVAL BOARD FOR XE8802AMI035LF
• Manufacturer: Semtech
• Type: MCUr

Specifications of XE8000EV110

• Contents: Fully Assembled Evaluation Board
• For Use With/related Products: XE88LC02MI035
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

The CkRcExt clock is the RC oscillator or external clock. The clocks below 32kHz can be derived from the RC
oscillator, the external clock source or the crystal oscillator (see the documentation of the clock block). A separate
external clock source can be delivered on PortA for each individula counter.
The external clock sources can be debounced or not by properly setting the PortA configuration registers.
Additionally, the external clock sources can be divided by two in the counter block, thus enabling higher external
clock frequencies, by setting the CntXExtDiv bits in the RegCntOn register.
Switching between an internal and an external clock source can only be performed while the counter is stopped.
The enabling or disabling of the external clock frequency division can only be performed while the counter using
this clock is stopped, or when this counter is running on an internal clock source.
20.8 Counter mode selection
Each counter can work in one of the following modes:
The counters A and B or C and D can be cascaded or not. In cascaded mode, A and C are the LSB counters while
B and D are the MSB counters.
Table 20-12 shows the different operation modes of the counters A and B as a function of the mode control bits.
For all counter modes, the source of the down or upcount selection is given (either the bit CntADownUp or the bit
CntBDownUp). Also, the mapping of the interrupt sources IrqA and IrqB and the PWM output on PB(0) in these
different modes is shown.
Table 20-13 shows the different operation modes of the counters C and D as a function of the mode control bits.
For all counter modes, the source of the down or upcount selection is given (either the bit CntCDownUp or the bit
© Semtech 2006
1) Counter, downcount & upcount
2) Captured counter, downcount & upcount (only counters A&B)
3) PWM, downcount & upcount
4) Captured PWM, downcount and upcount
CascadeAB
0
1
0
1
0
1
0
1
CountPWM0
0
0
1
1
0
0
1
1
CapFunc(1:0)
Table 20-12: Operating modes of the counters A and B
00
00
00
00
1x
x1
1x
x1
1x
x1
1x
x1
or
or
or
or
XE8802 Sensing Machine Data Acquisition MCU
Counter 8b
Downup: A
Downup: A
Downup: A
Captured counter 16b AB
Downup: A
Counter A
counter 8b
Captured 10 – 16b PWM
(captured value on 16b)
Captured
Captured
PWM 8b
PWM 8b
mode
PWM 10 – 16b AB
Counter 16b AB
Downup: A
Downup: A
Downup: A
Downup A
20-6
Counter 8b
Downup: B
Counter 8b
Downup: B
Downup: B
Downup: B
Counter B
counter 8b
counter 8b
Captured
Captured
with ZoomingADC™ and LCD driver
mode
Counter
Counter
Capture
Capture
Capture
Capture
source
IrqA
AB
AB
AB
A
A
A
-
-
Counter
Counter
Capture
Capture
Capture
Capture
source
IrqB
AB
AB
B
B
B
B
-
-
PWM AB
PWM AB
function
PWM A
PWM A
PB(0)
PB(0)
PB(0)
PB(0)
PB(0)
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