MPC555 / MPC556
ELECTRICAL CHARACTERISTICS
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
G-62
Figure G-38 MPWMSM Interrupt Flag to MPWMO Output Pin Falling Edge
Timing Diagram
G.21.2 MMCSM Timing Characteristics
Table G-23 MMCSM Timing Characteristics
(All delays are in IMB clock periods.)
Characteristic
Symbol
Min
Max
MMCSM Input Pin Period
t
PPER
4
—
MMCSM Pin Low Time
t
PLO
2
—
MMCSM Pin High Time
t
PHI
2
—
Clock Pin to Counter Bus Increment
t
PCCB
1
2
Load Pin to New Counter Bus Value
t
PLCB
1
2
Clock Pin to PINC Delay
t
PINC
1
2
Load Pin to PINL Delay
t
PINL
1
2
Counter Bus Resolution
t
CBR
–
1
NOTES:
1. Minimum output resolution depends on MMCSM and MCPSM prescaler settings.
2
2
2. Maximum resolution is obtained by setting CPSMPSL[3:0] = 0x2 and MMCSMSCR_CP[7:0] = 0xFF.
Counter Bus Overflow Reload to Interrupt Flag
t
CBFLG
1
MCPSM Enable to Counter Bus Increment
t
MCMP
(256 – MMCSMSCR_CP) * MCPSMS 2
3
3. When MCPSMSCR_PSL = 0x0000, this gives a prescale value of 16 and it is 16 which should be used in these
calculations. When MCPSMSCR_PSL = 0x0001, the CPSM is inactive.
MMCSM Enable to Counter Bus Increment (MIN)
4
4. The exact timing from MMCSM enable to the pin being set depends on the timing of the MMCSMSCR register
write and the MCPSM vs_pclk. The MMCSM enable is taken to mean the MMCSMSCR_CLS[1:0] being written
to 2‘b11.
t
MCME
4 + MCPSMSCR_PSL*
(255 – MMCSMSCR_CP)
3
MMCSM Enable to Counter Bus Increment (MAX)
4
t
MCME
4 + MCPSMSCR_PSL
*
(255 – MMCSMSCR_CP) + (MCPSMSCR_PSL
– 1)
3
f
SYS
t
FLGP
MPSMO pin output
≈
MPWMSM interrupt flag
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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