dsp56800e Freescale Semiconductor, Inc, dsp56800e Datasheet - Page 29

• Manufacturer Part Number: dsp56800e
• Description: 16-bit Digital Signal Controller Core
• Manufacturer: Freescale Semiconductor, Inc

Conventions
This document uses the following notational conventions:
Freescale Semiconductor
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Bits within registers are always listed from most significant bit (MSB) to least significant bit (LSB).
Bits within a register are formatted AA[n:0] when more than one bit is involved in a description.
For purposes of description, the bits are presented as if they are contiguous within a register.
However, they are not always contiguous. Refer to the programming-model diagrams or to the
programmer’s sheets to find the exact location of bits within a register.
When a bit is described as set, its value is set to one. When a bit is described as cleared, its value is
set to zero.
In graphic displays of registers, the following definitions of notation apply:
—
—
—
A pin or signal that is asserted low (made active when pulled to ground) has a bar over its name.
For example, the SS0 pin is asserted low.
Hexadecimal values are preceded by a dollar sign ($), as follows: $FFFB is the X memory address
for the interrupt priority register (IPR).
Unless noted otherwise, M designates the value 2
Memory addresses in the separate program and data memory spaces are differentiated by a
one-letter prefix. Data memory addresses have an X: prefix, while program memory addresses have
a P: prefix. For example, P:$0200 indicates a location in program memory. The terms data memory
and X memory are used interchangeably, and the terms program memory and P memory are used
interchangeably.
Code examples are displayed in a monospaced font, as follows:
Grey bit:
TYPE:
–
–
–
RESET
–
–
–
–
r
w
rw
0
1
?
—
: Read-only. Writing this bit has no effect.
BFSET #$0007,X:PCC ; Configure:
: Will reset to a logic 0.
: Will reset to a logic 1.
: The reset state is undefined.
: Write-only.
: The reset state depends on individual chip implementation.
: Standard read/write bit. Only software (or a hardware reset) can change the bit’s value.
The bit’s type defines its behavior. Possible values include:
: The reset value of the bit. Possible values include:
An unimplemented bit that always reads as zero. Writing has no effect.
; MISO0, MOSI0, SCK0 for SPI master
; ~SS0 as PC3 for GPIO
About This Book
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and K designates the value 2
10
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