AD8324

Rev. 0 | Page 14 of 16

OVERSHOOT ON PC PRINTER PORTS

The data lines on some PC parallel printer ports have excessive

overshoot, which may cause communications problems when

presented to the CLK pin of the AD8324. The evaluation board

was designed to accommodate a series resistor and shunt

capacitor (R9 and C5 in Figure 29) to filter the CLK signal if

required. For parallel ports with logic levels above 3.3 V, R9 and

C5 may be used as an attenuator.

INSTALLING VISUAL BASIC CONTROL SOFTWARE

Install the CabDrive_24 software by running the setup.exe file

on disk one of the AD8324 evaluation software. Follow the on-

screen directions and insert disk two when prompted. Choose

the installation directory and then select the icon in the upper

left to complete the installation.

RUNNING AD8324 SOFTWARE

To load the control software, go to START, PROGRAMS,

CABDRIVE_24 or select the AD8324.exe file from the installed

directory. Once loaded, select the proper parallel port to

communicate with the AD8324 (Figure 27).

Figure 27. Parallel Port Selection

CONTROLLING GAIN/ATTENUATION

OF THE AD8324

The slide bar controls the gain/attenuation of the AD8324,

which is displayed in dB and in V/V. The gain scales 1 dB per

LSB. The gain code from the position of the slide bar is

displayed in decimal, binary, and hexadecimal (Figure 28).

Figure 28. Control Software Interface

TRANSMIT ENABLE AND SLEEP MODE

The Transmit Enable and Transmit Disable buttons select the

mode of operation of the AD8324 by asserting logic levels on

the asynchronous TXEN pin. The Transmit Disable button

applies Logic 0 to the TXEN pin, disabling forward transmis-

sion. The Transmit Enable button applies Logic 1 to the TXEN

pin, enabling the AD8324 for forward transmission. Checking

the Enable SLEEP Mode checkbox applies Logic 0 to the asyn-

chronous SLEEP pin, setting the AD8324 for SLEEP mode.

MEMORY FUNCTIONS

The Memory section of the software provides a way to alternate

between two gain settings. The X–>M1 button stores the

current value of the gain slide bar into memory, while the RM1

button recalls the stored value, returning the gain slide bar to

the stored level. The same applies to the X–>M2 and RM2

buttons.