MC68HC908MR8 Datasheet, PDF (319/372 Pages) Motorola, Inc – Microcontrollers

Analog-to-Digital Converter (ADC)
I/O Registers
18.9 I/O Registers
These I/O registers control and monitor operation of the ADC:
• ADC status and control register (ADSCR)
• ADC data registers (ADRH and ARDL)
• ADC control register (ADCR)
• ADC clock register (ADCLK)
18.9.1 ADC Status and Control Register
These paragraphs describe the function of the ADC status and control
register (ADSCR). Writing ADSCR aborts the current conversion and
initiates a new conversion.
Ad-
dress:
$0040
Bit 7
6
5
4
3
2
1
Bit 0
Read:
COCO
Write:
AIEN
ADCO ADCH4 ADCH3 ADCH2 ADCH1 ADCH0
Reset: 0
0
0
1
1
1
1
1
Figure 18-3. ADC Status and Control Register (ADSCR)
COCO — Conversions Complete Bit
When AIEN bit is a logic 0, the COCO is a read-only bit which is set
each time a conversion is completed except in the continuous
conversion mode where it is set after the first conversion. This bit is
cleared whenever the ADC status and control register is written or
whenever the ADC data register is read.
If AIEN bit is a logic 1, the COCO is a read/write bit which selects the
CPU to service the ADC interrupt request. Reset clears this bit.
1 = Conversion completed (AIEN = 0) interrupt (AIEN = 1)
0 = Conversion not completed (AIEN = 0)/CPU interrupt (AIEN = 1)
MC68HC908MR8 — Rev 4.1
Freescale Semiconductor
Analog-to-Digital Converter (ADC)
Technical Data
319