mc68hc705c9a Freescale Semiconductor, Inc, mc68hc705c9a Datasheet - Page 42

• Manufacturer Part Number: mc68hc705c9a
• Description: M68hc05 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Resets
COPF — Computer Operating Properly Flag
CME — Clock Monitor Enable Bit
COPE — COP Enable Bit
CM1 — COP Mode Bit 1
CM0 — COP Mode Bit 0
Bits 7–5 — Not Used
5.6 MC68HC05C12A Compatible COP
This COP is implemented with an 18-bit ripple counter. This provides a timeout period of 64 milliseconds
at a bus rate (f
re-initialized in the same fashion as a power-on reset or reset.
42
Reading the COP control register clears COPF.
This bit is readable any time, but may be written only once.
This bit is readable any time. COPE, CM1, and CM0 together may be written with a single write, only
once, after reset. This bit is cleared by reset.
Used in conjunction with CM0 to establish the COP timeout period, this bit is readable any time. COPE,
CM1, and CM0 together may be written with a single write, only once, after reset. This bit is cleared by
reset.
Used in conjunction with CM1 to establish the COP timeout period, this bit is readable any time. COPE,
CM1, and CM0 together may be written with a single write, only once, after reset. This bit is cleared by
reset.
These bits always read as 0.
1 = COP or clock monitor reset has occurred.
0 = No COP or clock monitor reset has occurred.
1 = Clock monitor enabled
0 = Clock monitor disabled
1 = COP enabled
0 = COP disabled
op
$001E
Reset:
Read:
Write:
CM1
0
0
1
1
) of 2 MHz. If the COP should time out, a system reset will occur and the device will be
Bit 7
CM0
0
0
0
1
0
1
MC68HC05C9A Advance Information Data Sheet, Rev. 4.1
Figure 5-5. COP Control Register (COPCR)
= Unimplemented
6
0
0
f
op
Table 5-1. COP Timeout Period
/2
15
Divide By
16
64
1
4
5
0
0
COPF
U
4
U = Undetermined
Timeout Period
(f
osc
CME
131.07 ms
524.29 ms
2.097 sec
32.77 ms
3
0
= 2.0 MHz)
COPE
2
0
Timeout Period
(f
CM1
osc
1
0
262.14 ms
1.048 sec
16.38 ms
65.54 ms
= 4.0 MHz)
Freescale Semiconductor
Bit 0
CM0
0