NXP Semiconductors freescale semiconductor ColdFire MCF51CN128 Series, Справочное руководство

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MCF51CN128 Reference Manual
, Rev. 6
Freescale Semiconductor 15-1
Chapter 15
Analog-to-Digital Converter (ADC12)
15.1 Introduction
The 12-bit analog-to-digital converter (ADC) is a successive approximation ADC designed for operation
within an integrated microcontroller system-on-chip.
NOTE
• MCF51CN128 series devices do not include stop1 mode and pin control
registers. Ignore references to stop1 and pin control registers. For details
on low-power mode operation, refer to
Table 3-5 in Chapter 3, “Modes
of Operation ”. For details on register memory map, refer to Table 4-3 in
Chapter 4, “Memory ”.
• Use pin mux control registers from Section 2.3, “Pin Mux Controls ” to
assign ADC signals to the MCF51CN128 package pins.
• Most pin functions default to GPIO and must be software configured
before using ADC.
15.1.1 ADC Clock Gating
The bus clock to the ADC can be gated on and off using the SCGC1[ADC] bit (see Section 5.7.10, “System
Clock Gating Control 1 Register (SCGC1)” ). This bit is set after any reset that enables the bus clock to this
module. To conserve power, the SCGC1[ADC] bit can be cleared to disable the clock to this module when
not in use. See
Section 5.6, “Peripheral Clock Gating,” for details.
15.1.2 Module Configurations
This section provides information for configuring the ADC on this device.
15.1.2.1 Channel Assignments
The ADC channel assignments for this device are shown in Table 15-1 . Reserved channels convert to an
unknown value.