DdsModTerm software for AD9850/51 modules

🔘In the post 📮dated 📅27 July 2023, about how a µ-controller and a smart phone🖁 App could be used to upload 🠝 configuration settings to  modules based on AD9850 and AD9851 DDS chips in order to generate a frequency, it was briefly mentioned that  a USB dongle and pc interface software was another method in use here. As that software has recently been updated it would now be a good time to give a description of that method also.

The SpacerLabs dedicated pc 💻software called "DdsModTerm" is the user interface and was first released in about 2015. Since then there have been 15 revisions; the latest appearing this month.

'DdsModTerm' user interface

The clock 🕰frequency and the required output frequency and phase are entered, either manually or by recall from memory. By clicking 'Confirm', the software generates the 5 configuration bytes required from the user input data. In the example in the image above the output frequency is 137700Hz & bytes hexadecimal 00C88AC604. The pc 💻is connected to the serial data interface of the DDS module board via a COM port and the SpacerLabs USB-SPI dongle. Clicking 'Update DDS' then uploads the bytes using  SPI protocol to the registers of the DDS chip and the programmed frequency  ∿  is then present on the output. 

(L) USB-SPI dongle (R) AD9851 DDS chip evaluation board on adaptor

Other features of the software include up/down step 🪜tuning, slider tuning control, eeprom view, 3 memories for storing frequency, saving custom clock🕓, alias frequencies calculated, and general purpose output ( GPO ) toggling on/off.

The dongle and software are available from us. Post a comment, contact us by email or use the form below to receive more information. Note that both AD9850 & AD9851 DDS devices are supported.🔘

( Click on images to enlarge detail. )

SPI = Serial Peripheral Interface, 3-wire bus.

AD9850, AD9851 : 🔗Analog Devices Inc. parts, 32-bit CMOS Direct Digital Synthesiser (DDS) chips.

Webserver for the Greenhouse Gas Sensors

🔘 Carbon Dioxide, CO2, and Methane, CH4, are present in the atmosphere in part due to burning fossil fuels 🏭, and farming 🐂( particularly livestock ). They are potent 'greenhouse' gases as they have a significant impact on global warming, which drives climate change.

A new WiFi version of the Greenhouse Gas Monitoring System, ( 📅28.07.2022, 5.01.2023 & 18.02.2024 ) has been completed, incorporating a web 🕸 server having an embedded webpage. The firmware and webpage were developed along very similar lines to that used recently with the "Solarometer" 🔅( 📅13.10.2024 ); the latter using html and CSS *.

However, as the outdoor location of the gas sensors, ( type MQ-4 for CH4, type MQ-135 for CO2 ), will always be within the coverage area of an existing WiFi network access point, ( AP ), the system has been configured as a station ( STA ) on that network, and assigned the IP address 192.168.1.49.

Webpage opened in a smart phone's browser

The concentration ( parts per million, ppm ) measurements📏 are updated in real-time 🕔, and can be quickly viewed on a mobile device's🖁 browser, saving time over logging in to cloud ☁ based repositories, if historical data are not required.

Another way is to use the new SpacerLabs custom App "Greenhouse_Gas_Viewer v1.nn", for Android devices.

Displaying ppm measurements using the App

In this case the webpage itself ( /root directory ) is not displayed. Only the sub-directories ( /CH4ppm & /CO2ppm ), which are the place-holders for the CH4 and CO2 concentration data, are read by the App and the data held therein displayed.🔘

* CSS = Cascading Style Sheets - used to add style attributes to an html document.