Demonstration, Design, Evaluation, Investigation and Implementation
. . . . . . the EV8500 EvKit and DAA interface designs
a single board product comprising a CMX850 Communications Controller, line interface components, firmware and a serial communications port
EV8500 Evaluation Kit
n
Includes CMX850 IC for Product Evaluation
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Fully Isolated 2-Wire Line-Interface for FCC68 or CTR21 (DAA)
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Modem Calling/Answering and CLI Firmware
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Full Access to Unused CMX850 (80C51) Ports
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‘AT’ Command Compatible Firmware
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Control via PC Terminal Emulator
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Opto-Isolated ‘Ring Detect’ Circuitry and ‘Hook’ Relay
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Keyboard Encoder (16 x 8 matrix)
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8kB Internal RAM with 4M-bit (512kB) External Flash and 64kB External RAM
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Pre-Loaded Operating Software; Future Upgrades will be Available from the CML Website
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On-Board Flash Reprogramming
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Dual Analogue-to-Digital (ADC) Inputs
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Dual Low-Power PWM Outputs
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User’s On-Board Design and Prototyping Area
EV8500 EvKit for CMX850
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Space for Optional Telco-Specific Components
Telecom Interfacing with a DAA
As a stand-alone product, the CMX850 is intended to communicate via a telephone line. The connection to the line is via a special interface circuit that is often referred to as a
Data Access Arrangement (DAA). CML has available, on its web site, two DAA designs catering for the CMX850 within CTR21 and FCC Part 68 installations.
DAA Interface Designs for the CMX8500
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Line Interface Circuits (DAA) for CTR21 and FCC Part 68
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Ring Detect
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Hook Switch
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Line-in-Use Detect
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Parallel Phone Detect
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CLI Capability
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Example (Pre-Loaded Operating Software) µC source code to be run in the CMX850
external Flash/RAM is available from the EV8500
EvKits
page
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Design Information Available from:
www.cmlmicro.com/products/applications/Ap850_DAA.PDF
PSTN
On Hook Rx
Multiple I/O
External
Peripherals
Multiple IRQs
CMX850
Off Hook Rx
Ring Signal
Tx
‘C-BUS’
emulation
Data
Access
Arrangement
V.22bis
Modem
80C51
µC
Internal
Peripherals
Memory
Memory
Simple Layout with Line Interface DAA Reference Design
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CMLMICRO [ CML MICROCIRCUITS ]
