MC68HC812A4 Datasheet, PDF (290/342 Pages) Motorola, Inc – 16-bit device composed of standard on-chip peripheral modules connected by an intermodule bus. Modules include

Analog-to-Digital Converter (ATD)
Addr.
$007C
$007E
Register Name
Bit 7
6
5
ATD Result Register 6
(ADR6H)
See page 300.
Read:
Write:
Reset:
ADRxH7
ADRxH6
ADRxH5
ATD Result Register 7
(ADR7H)
See page 300.
Read:
Write:
Reset:
ADRxH7
ADRxH6
ADRxH5
= Unimplemented
4
3
ADRxH4 ADRxH3
Indeterminate
ADRxH4 ADRxH3
Indeterminate
2
ADRxH2
ADRxH2
1
ADRxH1
ADRxH1
Bit 0
ADRxH0
ADRxH0
Figure 16-2. ATD I/O Register Summary (Sheet 3 of 3)
16.6 Functional Description
A single conversion sequence consists of four or eight conversions,
depending on the state of the select 8-channel mode bit, S8CM, in ATD
control register 5 (ATDCTL5). There are eight basic conversion modes.
In the non-scan modes, the sequence complete flag, SCF, is set after
the sequence of four or eight conversions has been performed and the
ATD module halts.
In the scan modes, the SCF flag is set after the first sequence of four or
eight conversions has been performed, and the ATD module continues
to restart the sequence.
In both modes, the CCF flag associated with each register is set when
that register is loaded with the appropriate conversion result. That flag is
cleared automatically when that result register is read. The conversions
are started by writing to the control registers.
The ATD control register 4 selects the clock source and sets up the
prescaler. Writes to the ATD control registers initiate a new conversion
sequence. If a write occurs while a conversion is in progress, the
conversion is aborted and ATD activity halts until a write to ATDCTL5
occurs.
The ATD control register 5 selects conversion modes and conversion
channel(s) and initiates conversions.
MC68HC812A4 — Rev. 3.0
290
Analog-to-Digital Converter (ATD)
Advance Information
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