mc68hc908lb8 Freescale Semiconductor, Inc, mc68hc908lb8 Datasheet - Page 108

• Manufacturer Part Number: mc68hc908lb8
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

High Resolution PWM (HRP)
P[10:0] — 11-Bit Period Value
STEP[4:0] — 5-Bit Dithering Step Value
10.8.4 HRP Deadtime Register
This read/write register contains an 8-bit value corresponding to the number of HRPCLK cycles that will
be subtracted from the logic 1 level of the TOP and BOT output signals to provide deadtime between the
two signals.
10.8.5 Frequency Dithering HRP Timebase Registers
The two read/write frequency dithering timebase registers HRPTBH:HRPTBL contain a 16-bit value used
to determine the time base for switching between the two dithering frequencies. The timebase is
calculated from the following formula:
Writes to the high byte (HRPTBH) are stored in a latch until the low byte (HRPTBL) is written. Both
registers are then updated simultaneously. This prevents glitches occurring on the output signal.
108
Address: $0056
Address: HRPTBH — $0057
Reset:
Reset:
Reset:
Reset:
Read:
Read:
Read:
Read:
Write:
Write:
Write:
Write:
Frequency Dithering Timebase (seconds)
Figure 10-14. HRP Timebase Registers (HRPTBH:HRPTBL)
Figure 10-12. HRP Period Registers (HRPPERH:HRPPERL)
Bit 15
TB15
Bit 7
DT7
Bit 7
TB7
P2
0
0
0
0
Figure 10-13. HRP Deadtime Register (HRPDT)
TB14
DT6
TB6
P1
14
0
0
0
0
6
6
Dead Time
HRPTBL — $0058
MC68HC908LB8 Data Sheet, Rev. 1
TB13
DT5
TB5
P0
13
0
5
0
0
5
0
=
------------------------- -
HRPCLK
HRPDT
STEP4
TB12
DT4
TB4
12
0
4
0
0
4
0
=
HRPTBH:HRPTBL
------------------------------------------------- -
STEP3
TB11
DT3
TB3
11
0
1
0
0
3
3
HRPCLK
STEP2
TB10
DT2
TB2
10
0
0
0
0
2
2
STEP1
DT1
TB9
TB1
0
0
0
0
1
9
1
Freescale Semiconductor
STEP0
Bit 0
Bit 8
Bit 0
DT0
TB8
TB0
0
0
0
0
(EQ 10-14)
(EQ 10-15)