P
RELIMINARY
P
RODUCT
S
PECIFICATION
1
Z89175
Z89176 (R
OMLESS
)
V
OICE
P
ROCESSING
C
ONTROLLERS
FEATURES
Device
Z89175
Z89176
ROM
(KB)
24
-
RAM*
(Bytes)
256
256
I/O
Lines
47
31
Voltage
Range
4.5V to 5.5V
4.5V to 5.5V
s
s
s
s
s
s
s
s
s
s
s
s
s
1
2
Clock Speeds of 20.48 or 29.49 MHz
16-Bit Digital Signal Processor (DSP)
8K Word DSP Program ROM
512 Words On-Chip DSP RAM
8-Bit A/D Converter with up to 16 kHz Sample Rate
10-Bit PWM D/A Converter
Six Vectored, Prioritized Z8 Interrupts
Three Vectored, Prioritized DSP Interrupts
Two DSP Timers to Support Different A/D and D/A
Sampling Rates
IBM
®
PC-Based Development Tools
Developer’s Toolbox for T.A.M. Applications
Note:
*General-Purpose
s
s
s
Watch-Dog Timer and Power-On Reset
Improved Low Power Stop Mode
On-Chip Oscillator which Accepts a Crystal
or External Clock Drive
Improved Global Power-Down Mode
s
Low Power Consumption - 200 mW (typical)
Two Comparators
RAM and ROM Protect
On-Board Oscillator for 32.768 kHz Real-Time Clock
s
s
GENERAL DESCRIPTION
The Z89175/176 is a fully integrated, dual processor con-
troller designed for voice processing applications. The I/O
control processor is a Z8
®
with 24 KB of program memory,
two 8-bit counter/timers, and up to 47 I/O pins. The DSP is
a 16-bit processor with a 24-bit ALU and accumulator,
512x16 bits of RAM, single cycle instructions, and 8K
words of program ROM. The chip also contains a half-flash
8-bit A/D converter with up to a 16 kHz sample rate and a
10-bit PWM D/A converter. The sampling rates for the con-
verters are programmable. The precision of the 8-bit A/D
can be extended by resampling the data at a lower rate in
software. The Z8 and DSP processors are coupled by
mailbox registers and an interrupt system. DSP or Z8 pro-
grams can be directed by events in each other’s domain.
The Z89176 is the ROMless version of the Z89175. How-
ever, the on-chip DSP is not ROMless.
Notes:
All Signals with a preceding front slash, "/", are ac-
tive Low, e.g., B//W (WORD is active Low); /B/W (BYTE is
active Low, only).
Power connections follow conventional descriptions be-
low:
Connection
Power
Ground
Circuit
V
CC
GND
Device
V
DD
V
SS
DS97TAD0100
PRELIMINARY
1
Z89175/Z89176
Voice Processing Controllers
Zilog
GENERAL DESCRIPTION
(Continued)
Z8 Core Processor
The on-chip Z8 is Zilog’s 8-bit microcontroller core with an
Expanded Register File to allow access to register-
mapped peripheral and I/O circuits. The Z8 offers a flexible
I/O scheme, an efficient register and address space struc-
ture and a number of ancillary features which makes it ide-
ally suited for high-volume processing, peripheral control-
lers and consumer applications.
For applications demanding powerful I/O capabilities, the
Z89175 provides 47 pins dedicated to input and output.
These I/O lines are grouped into six ports. Each port is
configurable under software control to provide timing, sta-
tus signals and parallel I/O with or without handshake.
Four basic memory resources for the Z8 are available to
support a wide range of configurations: Program Memory,
Register File, Data Memory, and Expanded Register File.
The Z8 core processor is supported by an efficient register
file that allows any of 256 on-board data and control regis-
ters to be either the source and/or the destination of almost
any instruction. This unique architecture eliminates tradi-
tional microprocessor Accumulator bottlenecks and per-
mits rapid content switching.
The Register File is composed of 236 bytes of general-pur-
pose registers, four I/O port registers, and 15 control and
status registers. The Expanded Register File consists of
mailbox registers, WDT mode register, DSP Control regis-
ter, Stop-Mode Recovery register, Port Configuration reg-
ister, and the control and data registers for Port 4 and Port
5. Some of these registers are shared with the DSP.
To unburden the software from supporting real-time prob-
lems such as counting/timing and data communication, the
Z8 offers two on-chip counter/timers with a large number
of user-selectable modes.
Watch-Dog Timer and Stop-Mode Recovery features are
software driven by setting specific bits in control registers.
STOP and HALT instructions support reduced power op-
eration. The low-power Stop Mode allows parameter infor-
mation to be stored in the register file if power fails. An ex-
ternal capacitor or battery will retain device memory and
power the 32 kHz timer.
DSP Coprocessor
The DSP coprocessor is a second generation, 16-bit two’s
complement CMOS Digital Signal Processor (DSP). Most
instructions, including multiply and accumulate, are ac-
complished in a single clock cycle. The processor contains
two on-chip data RAM blocks of 256 words, a 8K word pro-
gram ROM, 24-bit ALU, 16x16 multiplier, 24-bit Accumula-
tor, shifter, six-level stack, three vectored interrupts and
two inputs for conditional program jumps. Each RAM block
contains a set of four pointers which can be incremented
or decremented automatically to affect hardware looping
without software overhead. The data RAMs can be simul-
taneously addressed and loaded to the multiplier for a true
single-cycle scalar multiply.
Four external DSP registers are mapped into the expand-
ed register file of the Z8. Communication between the Z8
and the DSP occurs through those common registers
which form the mailbox registers.
The analog output is generated by a 10-bit resolution
Pulse Width Modulator. The PWM output is a digital signal
with CMOS output levels. The output signal has a resolu-
tion of 1 in 1024 with a sampling rate of 16 kHz (XTAL =
20.48 MHz). The sampling rate can be changed under
software control and can be set at 10 and 16 kHz. The dy-
namic range of the PWM is from 0 to 4V.
An 8-bit resolution half-flash A/D converter is provided.
The conversion is conducted with a sampling frequency of
16 kHz. (XTAL = 20.48 MHz) in order to provide oversam-
pling. The input signal is 4V peak to peak.
Two additional timers (Timer2 and Timer3) have been
added to support different sampling rates for the A/D and
D/A converters. These timers are free-running counters
that divide the crystal frequency to the appropriate sam-
pling of frequency. Two DSP I/O pins: DSP0, DSP1 are
provided for application.
2
PRELIMINARY
DS97TAD0100