Motorola DSP56303 User Manual page 19

Table 1-1. High True/Low True Signal Conventions (Continued)
Signal/Symbol
PIN
PIN
Note: 1. PIN is a generic term for any pin on the chip.
2. Ground is an acceptable low voltage level. See the appropriate data sheet for the range of acceptable low
voltage levels (typically a TTL logic low).
3. V is an acceptable high voltage level. See the appropriate data sheet for the range of acceptable high
CC
voltage levels (typically a TTL logic high).
Pins or signals that are asserted low (made active when pulled to ground) are indicated
like this:
— In text, they have an overbar: for example,
— In code examples, they have a tilde in front of their names. In Example 1-1, line 3
refers to the
Sets of signals are indicated by the first and last signals in the set, for instance
HAD[0–7].
"Input/Output" indicates a bidirectional signal. "Input or Output" indicates a signal
that is exclusively one or the other.
Code examples are displayed in a monospaced font, as shown in Example 1-1.
BFSET
Hex values are indicated with a $ preceding the hex value, as follows: $FFFFFF is the
X memory address for the core interrupt priority register.
The word "reset" is used in four different contexts in this manual:
— the reset signal, written as
— the reset instruction, written as RESET
— the reset operating state, written as Reset
— the reset function, written as reset
Logic State
True
False
signal (shown as ~SS0).
SS0
Example 1-1. Sample Code Listing
#$0007,X:PCC; Configure:
; MISO0, MOSI0, SCK0 for SPI master
; ~SS0 as PC3 for GPIO
RESET
Overview
Signal State
Asserted
Deasserted
is asserted low.
RESET
Manual Conventions
Voltage
V
CC
Ground
line 1
line 2
line 3
1-3