Datasheet

Analog Comparator (S08ACMPV2)
MC9S08JM16 Series Data Sheet, Rev. 2
Freescale Semiconductor 131
• An 8-bit status and control register
Refer to the direct-page register summary in the memory section of this data sheet for the absolute address
assignments for all ACMP registers.This section refers to registers and control bits only by their names.
Some MCUs may have more than one ACMP, so register names include placeholder characters to identify
which ACMP is being referenced.
9.3.1.1 ACMP Status and Control Register (ACMPSC)
ACMPSC contains the status flag and control bits which are used to enable and configure the ACMP.
76543210
R
ACME ACBGS ACF ACIE
ACO
ACOPE ACMOD
W
Reset:00000000
= Unimplemented
Figure 9-3. ACMP Status and Control Register
Table 9-2. ACMP Status and Control Register Field Descriptions
Field Description
7
ACME
Analog Comparator Module Enable — ACME enables the ACMP module.
0 ACMP not enabled
1 ACMP is enabled
6
ACBGS
Analog Comparator Bandgap Select — ACBGS is used to select between the bandgap reference voltage or
the ACMP+ pin as the input to the non-inverting input of the analog comparatorr.
0 External pin ACMP+ selected as non-inverting input to comparator
1 Internal reference select as non-inverting input to comparator
Note: refer to this chapter introduction to verify if any other config bits are necessary to enable the bandgap
reference in the chip level.
5
ACF
Analog Comparator Flag — ACF is set when a compare event occurs. Compare events are defined by ACMOD.
ACF is cleared by writing a one to ACF.
0 Compare event has not occurred
1 Compare event has occurred
4
ACIE
Analog Comparator Interrupt Enable — ACIE enables the interrupt from the ACMP. When ACIE is set, an
interrupt will be asserted when ACF is set.
0 Interrupt disabled
1 Interrupt enabled
3
ACO
Analog Comparator Output — Reading ACO will return the current value of the analog comparator output.
ACO
is reset to a 0 and will read as a 0 when the ACMP is disabled (ACME = 0).