Modular Input/Output Subsystem (MIOS14)
MPC561/MPC563 Reference Manual, Rev. 1.2
17-16
Freescale Semiconductor
17.7
MIOS14 Counter Prescaler Submodule (MCPSM)
The MIOS14 counter prescaler submodule (MCPSM) divides the MIOS14 clock (f
SYS
) to generate the
counter clock. It is designed to provide all the submodules with the same division of the main MIOS14
clock (division of f
SYS
). It uses a 4-bit modulus counter. The clock signal is prescaled by loading the value
of the clock prescaler register into the prescaler counter every time it overflows. This allows all prescaling
factors between 2 and 16. Counting is enabled by asserting MCPSMSCR[PREN]. The counter can be
stopped at any time by negating this bit, thereby stopping all submodules using the output of the MCPSM
(counter clock). A block diagram of the MCPSM is given in
.
The following sections describe the MCPSM in detail.
Figure 17-8. MCPSM Block Diagram
17.7.1
MCPSM Features
•
Centralized counter clock generator
8
SUPV
Supervisor data space selector — The SUPV bit tells if the address space from 0x30 6000 to
0x30 67FF in the MIOS14 is accessed at the supervisor privilege level (See
). When
cleared, these addresses are accessed at the unrestricted privilege level.
The SUPV bit is cleared by reset.
0 Unrestricted Data Space.
1 Supervisor Data Space.
9:15
—
Reserved. These bits are used for the IARB (interrupt arbitration ID) field in MIOS14
implementations that use hardware interrupt arbitration. These bits are not used on
MPC561/MPC563.
Table 17-5. MIOS14MCR Bit Descriptions (continued)
Bits
Name
Description
f
SYS
Prescaler
PREN
CP2
CP1
CP0
Decrementer
Clock
Register
Load
CP3
Enable
MCPSMSCR
4-bit
Overflow
Dec.
Counter Clock
= 1?
Summary of Contents for MPC561
Page 84: ...MPC561 MPC563 Reference Manual Rev 1 2 lxxxiv Freescale Semiconductor...
Page 144: ...Signal Descriptions MPC561 MPC563 Reference Manual Rev 1 2 2 46 Freescale Semiconductor...
Page 206: ...Central Processing Unit MPC561 MPC563 Reference Manual Rev 1 2 3 62 Freescale Semiconductor...
Page 302: ...Reset MPC561 MPC563 Reference Manual Rev 1 2 7 14 Freescale Semiconductor...
Page 854: ...Time Processor Unit 3 MPC561 MPC563 Reference Manual Rev 1 2 19 24 Freescale Semiconductor...
Page 968: ...Development Support MPC561 MPC563 Reference Manual Rev 1 2 23 54 Freescale Semiconductor...
Page 1144: ...Internal Memory Map MPC561 MPC563 Reference Manual Rev 1 2 B 34 Freescale Semiconductor...
Page 1212: ...TPU3 ROM Functions MPC561 MPC563 Reference Manual Rev 1 2 D 60 Freescale Semiconductor...
Page 1216: ...Memory Access Timing MPC561 MPC563 Reference Manual Rev 1 2 E 4 Freescale Semiconductor...