NXP Semiconductors MPC5566 - Default Chapter; External Signal Descriptions

Signal Description
MPC5566 Microcontroller Reference Manual, Rev. 2
Freescale Semiconductor 2-3
2.2 External Signal Descriptions
This section summarizes the external signal functions, the electrical characteristics, and pad configuration
settings for this device. The signal properties and electrical characteristics are set in the System Integration
Unit (SIU) Pad Configuration (PCR) registers.
2.2.1 Multiplexed Signals
Signal functions are multiplexed to each ball on the BGA in a function hierarchy: Primary, Main Primary,
Alternate, Second Alternate, and General Purpose Input/Output (I/O). For example, in the signal
PCSA[3]_SIND_GPIO[99], the primary signal function is PCSA[3], the first alternate signal function is
SIND, and the GPIO function is a generic General Purpose I/O signal. Multiplexing signal functions
allows for more flexibility when configuring the device, as well as providing compatibility with other
devices in the MPC5500 product family.
The primary signal function name is used in the Ball Grid Array (BGA) map to identify the location of the
ball, however, the primary signal function is not always valid for all devices. As shown in Figure 2-2, when
the primary signal function is not available on the device, a dash appears in the following Signal table
columns: Signal Functions, P/A/G, and I/O Type.
Figure 2-2. Primary Function Not Available on Device
The entries in the P/A/G column designate the position in the signal function hierarchy for multiplexed
functions. These symbols correspond to binary values for the Pin Assignment (PA) field in the SIU_PCR
registers that determine the active signal function. The PA field is from 1- to 3-bits wide, depending on the
PCR register. Figure 2-3 explains the symbol definitions used in the P/A/G column for Table 2-1.
Signal Names Signal Functions
P/
A/
G
I/O
Type
Volt ag e
Pad
Type
S
During
Reset
PCSA[3]_
21
SIND_
GPIO[99]
—
DSPI D data input
GPIO
—
A
G
—
I
I/O
VDDEH6 MH – / Up
Primary Functions
Secondary Functions
GPIO Functions are
No primary
Footnote
Ta bl e
Table 4-1. Signal Properties
are listed First
are alternate functions
general functions listed Last
function
available