A brief post to confirm that Talisman V2 will no longer require a seperate CPU, but will use the CPU that comes on the needed (WiFi and Bluetooth) radio module.
Earlier consideration had been given to the single core ESP-07, but this was upgraded to the more powerful dual core ESP-WROOM-32.
The above image shows the WiFi radio module – left hand is the top side view, right side is the rear view. It is 1 inch in height and thin.
This CPU also has more pins which makes it easier to wire connections to all the other components.
The new central processing unit (CPU) that will power the Talisman V2 is up and running! Yeah, whoop, whoop. This is significant because it implies / proves that ‘we have the technology’ (sorted) to wire up power to the chip, communicate to it in order to load an initial trivial program.
So it is now possible (for me) to use the new dual core CPU. With this first most basic of programs working, it is possible to move on with success adding more interesting programs.
In short, the rest of the firmware on the Talisman is just more of the same of this first program, whereas getting the first program required all the configuration, code editor program setup, coding language , compiler and other geekery.
This image shows a hand wired prototype that is used to confirm all electronic components. Of most interest is the right hand side white square with the two red push buttons. On this white square the WiFi radio module (with dual core CPU) can be seen within the right hand side white area. It is the metal covered square with the tall black square on it’s left. Actual size 1 inch wide.
In the centre of this photo is another smaller white square with a single core, slower less powerful WiFi module. This is not being used, since the more powerful dual core module is now working.
The other component of note is the new upgraded power regulator, also wired up and working to power the circuit. This can be seen on the small green square board with the two tan circular ‘lentil’ looking components towards the top row of the photo. The actual power regulator is the tiny small black rectangle in the middle of the green square.
The remaining components have all been wired up and used successfully on the previous V1 Talisman. The next task is to programming the new WiFi radio module with the dual core CPUs to communicate to the previously used components. (vibration motor, accelerometer, LEDs, battery charger.) Once this component confirmation is completed, the components can be arranged to fit on a printed circuit board with their tested wiring.
Following on from a great zoom conf call with Jean, Carolyn, Nader, Greg and Allan the following important dates for getting a beta trial prepared prior to the Cascadia retreat were entered into a Gnatt chart.
The key dates are:
14 March – Release of the Content Curriculum Course editor site.
26 March – Ship single functional (no apps) prototype V2 to Barre.
23 April – Release Portal for testing and bug detection.
30 April – Ship 9 Beta Talisman to Cascadia.
Exciting and busy few months!
The Talisman V2 is shifting the choice of the encapsulation or packaging of the internal electronics to other artistic people. it is suggested that one potential possible packaging could be the use of the end user mouldable Sugru.
A sample 3 pack of safe, family friendly Sugru has been ordered. The white color was choosen to allow the light from the colored LEDs on the electronics to shine through the hardened rubbery Sugru.
To ensure the waterproof seal and to avoid any shear stress ripping the electronics off the circuit board, a thin layer of clear soft rubbery “conformal coating” will be sprayed over the completed circuit board.
Coating the electronics in a paper thin layer of conformal coating will allow the encapsulated unit to receive thermal heating and cooling expansion and contraction movement, along with physical knock stress. The layer of rubbery conformal coating allows the components to squidge against the rubber layer.
Conformal coating is an expensive specialists coating, available in small quantities by 3M (via RS Components) as an aerosol spray dispenser can.