Signals

Internal Digital Power

VSSI

 

 

 

 

 

Shared with Other Modules

VDDI

 

 

 

 

 

Analog Power and Ground

VSSA

 

 

 

 

 

VDDA

 

 

 

 

 

 

 

 

 

 

 

 

 

Analog References

VRH

 

 

 

 

 

VRL

 

 

 

 

 

 

 

 

 

 

 

 

 

Port QB Analog Inputs

 

AN0/ANW/PQB0

 

 

 

 

 

 

 

 

 

 

 

 

AN1/ANX/PQB1

 

 

 

 

 

External MUX Inputs

 

 

 

 

 

 

 

AN2/ANY/PQB2

 

 

 

 

QB

Digital Inputs

 

 

 

 

 

 

 

 

 

 

AN3/ANZ/PQB3

 

 

 

 

 

 

 

 

 

 

 

PORT

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Port QA Analog Inputs

 

AN52/MA0/PQA0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

AN53/MA1/PQA1

 

 

 

 

 

 

 

 

 

 

External Trigger Inputs

 

 

 

 

 

 

 

QA

 

 

 

 

 

 

 

External MUX Address Outputs

 

AN55/ETRIG1/PQA3

 

 

 

 

 

 

 

 

 

Digital I/O

 

 

 

 

 

PORT

 

 

 

 

 

 

AN56/ETRIG2/PQA4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Analog

Mux and

Port Logic

Analog

Converter

Digital

Results

and

Control

Figure 27-2. QADC Input and Output Signals

27.4.1.2Port QA Digital Input/Output Signals

Port QA signals are referred to as PQA[4:3, 1:0] when used as a bidirectional 4-bit digital input/output port. These four signals may be used for general-purpose digital input or digital output.

Port QA signals are connected to a digital input synchronizer during reads and may be used as general-purpose digital inputs when the applied voltages meet high-voltage input (VIH) and low-voltage input (VIL) requirements.

Each port QA signal is configured as an input or output by programming the port data direction register (DDRQA). The digital input signal states are read from the port QA data register (PORTQA) when DDRQA specifies that the signals are inputs. The digital data in PORTQA is driven onto the port QA signals when the corresponding bits in DDRQA specify output. See Section 27.6.4.

27.4.2 Port QB Signal Functions

The four port QB signals can be used as analog inputs or as a 4-bit digital I/O port.

27.4.2.1Port QB Analog Input Signals

When used as analog inputs, the four port QB signals are referred to as AN[3:0].

MOTOROLA

Chapter 27. Queued Analog-to-Digital Converter (QADC)

27-5

Page 589
Image 589
Motorola MCF5281, MCF5282 Port QB Signal Functions, Port QA Digital Input/Output Signals, Port QB Analog Input Signals