Class _acb: analog comparator

A class _acb object is an analog comparator.

It is used in:

• ATtiny25/45/85 : acmp0

Interrupts

Class _acb objects can trigger the following IRQs:

• HW_IRQ(acmp0): comparator output event

Actions

configure:

Note When the analog comparator shares the analog multiplexer output with the ADC, the ADC must be turned off for the analog comparator to be able to use the analog multiplexer output.

hwa( configure, acmp0,
 
   [ edge,            falling
                    | rising
                    | both, ]
 
   [ positive_input,  (pin,ain0)
                    | bandgap,    ]
 
   [ negative_input,  (pin,ain1)
                    | (pin,adc0..3) ] );

Registers

Hardware registers:

• csr: control/status register

Logical registers:

• acd: analog comparator disable (power management)
• acbg: analog comparator bandgap select
• aco: analog comparator output
• if: analog comparator interrupt flag
• ie: analog comparator interrupt enable
• acic: analog comparator input capture enable
• acis: analog comparator interrupt mode select