The VCNL3020 Breakout Board Rev 0 is complete. Added some vias to stitch the ground planes. I already have some ideas to make this breakout better. Going to add a solderable jumper and a space for a 3.3V regulator so it can be used with 5V I/O systems.
Just finished the first layout for the VCNL3020 Proximity Sensor. Will be uploading the design files once I give the board another look over. Board is .72″ x .65″ and can be a completely single sided board (shown two sided with another ground plane). I will probably stitch the two ground planes together with some vias before releasing the files.
The VCNL3020 is a integrated proximity sensor that works via infrared. Interface to the sensor is with i2c and it can measyure up to 200mm in distance. The only back draw to the sensor is the lack of ability to change the i2c address which can be a problem. Currently the schematic above only works with 3.3V systems. Adding a 3.3V regulator would fix that problem.
I have the first 5 Prop Dev Sticks boxed up for testers. I will be dropping them off at the post office tomorrow. Hopefully no hardware bugs pop up!
Also I am looking into adding more daily blogs posts. Content like app-notes, engineering design thoughts, and interesting parts.
The Propeller Development Stick Redux uses a AD7999 I2C ADC to add analog functionality to the Propeller. I used the Basic I2C Driver and then wrote two demo programs to demonstrate how to get data from the AD7999. The demos could be used with other devices from the AD799X series with proper changes to the defines.
AD7999 Round Robin Channel
AD7999 Select Channel
The round robin style enables all 4 channels then pulls the data in sequence. This makes the sampling faster as you do not need to write to the AD7999 every sample. The select channel demo writes to the AD7999 and tells it which channel to sample then gets the data. This is slower then the round robin style but you can request a specific channel.
Spent part of Saturday cleaning up the old Tektaonix 465 scope. Looks much better now. I reseated all the transistors and boards I could find in it but it still acts a bit flakey. Sometimes it will function perfectly then other times the sweep will start to go funky. Power supply might be the culprit.
I updated the PDS page with information on how to configure the FT230X EEPROM and the Propeller Tool IDE.
Template for FT230X EEPROM
You will need to download FT-Prog from FTDI. The FT230X needs to be flashed with this template for the Propeller Development Stick to function correctly.
Also the Propeller Tool needs a tweak to its options to make it use the RTS signal to reset the Propeller instead of the DTR signal (which the FT230X does not have). Do this by opening Propeller Tool and clicking Edit. At the bottom there is “Preferences”. Under the tab “Operation” there will be Propeller Reset Signal. Change it from “DTR” to “DTR & RTS”. Press accept to save the settings. Propeller GCC using SimpleIDE also allows you to change the reset signal in the general tab of properties.
I received a Tektaonix 465 last week from my friend Ben.
It is an old 100MHz analog scope. So far it all works. It needs some serious cleaning and some parts need to be reseated (had to wack the case to get it turned on) so I will do a tear down video this weekend.
I had to install the mail handling on the server. If you sent me an email the past 2 weeks I probably did not receive it.