Chapter 7 Analog-to-Digital Converter (ATD10B16CV4)
MC9S12XDP512 Data Sheet, Rev. 2.11
Freescale Semiconductor 339
7.3.2.14 Port Data Register 0 (PORTAD0)

The data port associated with the ATD is input-only. The port pins are shared with the analog A/D inputs

AN[15:8].

Read: Anytime
Write: Anytime, no effect

The A/D input channels may be used for general-purpose digital input.

Module Base + 0x000E
76543210
R PTAD15 PTAD14 PTAD13 PTAD12 PTAD11 PTAD10 PTAD9 PTAD8
W
Reset 11111111
Pin
Function AN15 AN14 AN13 AN12 AN11 AN10 AN9 AN8
= Unimplemented or Reserved

Figure 7-16. Port Data Register 0 (PORTAD0)

Table 7-25. PORTAD0 Field Descriptions

Field Description
7:0
PTAD[15:8]
A/D Channel x (ANx) Digital Input Bits— If the digital input buffer on the ANx pin is enabled (IENx = 1) or
channel x is enabled as external trigger (ETRIGE = 1, ETRIGCH[3-0] = x, ETRIGSEL = 0) read returns the
logic level on ANx pin (signal potentials not meeting VIL or VIH specifications will have an indeterminate value)).
If the digital input buffers are disabled (IENx = 0) and channel x is not enabled as external trigger, read returns
a “1”.
Reset sets all PORTAD0 bits to “1”.