MC68HC812A4 Datasheet, PDF (300/342 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)
SAR9–SAR0 — SAR Data Bits
Reads of this byte return the current value in the SAR. Writes to this
byte change the SAR to the value written. Bits SAR9–SAR2 reflect
the eight SAR bits used during the resolution process for an 8-bit
result. SAR1 and SAR0 are reserved to allow future derivatives to
increase ATD resolution to 10 bits.
RST — Reset Bit
When set, this bit causes all registers and activity in the module to
assume the same state as out of power-on reset (except for ADPU bit
in ATDCTL2, which remains set, allowing the ATD module to remain
enabled).
TSTOUT — Multiplex Output of TST3–TST0 (factory use)
TST3–TST0 — Test Bits 3 to 0 (reserved)
Selects one of 16 reserved factory testing modes
16.7.9 ATD Result Registers
ADR0H: $0070
ADR1H: $0072
ADR2H: $0074
ADR3H: $0076
ADR4H: $0078
ADR5H: $007A
ADR6H: $007C
ADR7H: $007E
Bit 7
6
5
4
3
2
1
Bit 0
Read: ADRxH7 ADRxH6 ADRxH5 ADRxH4 ADRxH3 ADRxH2 ADRxH1 ADRxH0
Write:
Reset:
Indeterminate
Figure 16-13. ATD Result Registers (ADR0H–ADR7H)
Read: Anytime
Write: Has no meaning or effect
MC68HC812A4 — Rev. 3.0
300
Analog-to-Digital Converter (ATD)
Advance Information
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