EV8680 Datasheet, PDF (14/39 Pages) CML Microcircuits – Evaluation Kit

Evaluation Kit for CMX868
EV8680
1.6.1.6 Line Protection
Line protection is provided by R2 (47Ω), R3 (47Ω), and D1 (Phillips BR211 series 140V). These
components are not fitted, but suitable values for UK applications are suggested in brackets. Wire
links which bypass R2 and R3 will need to be removed if these resistors are fitted.
1.6.2 Adjustments and Controls
Various line interface components around the evaluation devices are socketed to allow for user
adjustments. Discrete component sockets are also provided for Telco-specific components.
1.6.3 Firmware Description
The PIC16LC76-04/SP (OTP) µC fitted on the EV8680 evaluation kit has been programmed by CML
before shipment with the latest version of firmware. Please read the separate information sheet
(EK8680) and check the CML web site for firmware status. The latest source code and programming
file (EF8680xx.HEX, where xx represents the version number) can be downloaded from the CML web
site.
The serial communications firmware supplied in the PIC µC assumes the following configuration; 8
data bits, no parity, 1 stop bit and 19,200 baud with hardware flow control.
The firmware routine run at start-up and reset performs the following important tasks:
Peripheral Interrupt Initialisation
µC ports and I/O direction initialisation
Serial Communication Interface (SCI) initialisation
Serial Peripheral Interface (SPI) initialisation
Loads factory profile 0
Resets CMX868 evaluation device.
The message EF8680 Vx.x, will be displayed in the terminal emulator window when these tasks have
been completed.
The EV8680 evaluation board will send an error message (‘Invalid CMX868 Rev’) to the PC if an old
CMX868 device revision is detected. The latest EV8680 firmware is only designed to work with the
latest CMX868 device.
Note, the CMX868 device is always reset and powered up at the beginning of the negotiation or BERT
routines.
The firmware only supports DTMF dialling.
AT command echoing is an option available in the firmware and involves echoing the received
characters sent by the PC. The firmware also provides the option of sending result codes to the PC.
These responses can be in either an alpha or numeric form.
The AT command set for the EV8680 Evaluation kit is tabulated below. These commands can be
entered on a PC running Windows terminal emulator software, such as the ‘Hyper Terminal’ program
supplied with Windows 95/NT systems.
© 2000 Consumer Microcircuits Limited
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UM8680/2