I was out of town for most of the weekend, so I wasn't able to get much done. I worked on getting bluetooth audio working and so far that has been a bit of a challenge, but still appears to be within the realm of possibility. On the presumption that I'll get it working, I have been looking at some alternate layouts inside the calculator. Because of leaving out the audio board, I decided that I could probably now fit a USB port that will go directly to the raspberry pi onto the calculator, but I haven't decided if the HDMI port will be where the audio port was or if that's where I'll place the ...

This is just a short blog entry as I didn't have much time to work on my research. I now have the display working 100%. I got a little impatient and started digging in a little deeper myself. In the end I added spi_bcm2835 into /etc/modules to force SPI to start first and that fixed the issue. I posted my fix on the adafruit github for that issue, so hopefully that will help some other people out.

Another thing I realized that would make some more pins available is that I could just use Bluetooth Headphones. Then I could have my adjustable backlight pin back. I went ahead and ordered a broken ...

I went ahead and mapped out the circuit board today. It wasn't exactly the rows and columns that I was hoping for, but rather networks of circuitry. I counted 15 distinct networks plus the on button was separate. When I mapped them out in a spreadsheet, the bottom 8 rows are definitely in a matrix as expected. However, for the top 2 rows and the arrow keys, they use some of the row networks as columns and that's why I decided to map it out as networks (a term I took from Eagle regarding a series of connections all electrically attached) rather than rows and columns.

So what does this mean? Pro...

I feel like I'm very close. To start out, I found an alternative FBCP driver for the hardware combination I'm attempting to get working available at https://github.com/juj/fbcp-ili9341. I went through the initial build procedure and it seems to be working with a few exceptions:

After looking in the documentation, it explicitly says touchscreen will not work, but one may be able to get it working if they took a stab at it. After that, I switched back to the Adafruit FBCP. I found that if I run FBCP at the command line after booting it, it seems to work just fine with touch and everything. I tr...

I ended up getting my order of parts for my calculator, which I'm thinking of calling a Hackulator. One of the things I ordered was a mini HDMI port extender so I can hook it up to a monitor without taking apart the calculator and without having all of the ports exposed (though it is still an option at this point). I took all of the boards and the battery and I was able to fit them inside the case. After a little bit of moving items around inside, I'm pretty sure I know where I want all of the boards. For the new display board, I am able to fit it right behind the LCD display, so the extension...

It's worked! Once. I checked all of the connections and everything seemed to checkout fine. I booted it up and it did the same thing as it did yesterday with the black screen. So I figured it wouldn't hurt to try running the script again. It must need to probe something for the settings or my messing around with it may have messed something up, but it started working. As luck would have it, the very stiff HDMI cable I was using lifted the entire setup into the air and the LCD panel fell off. I attached it back on, but I still haven't been able to get it working. I switched to a regular HDMI ca...

I didn't have much time to work on it today, but I did discover one of the wires I used for repairing was attached to the wrong point. I moved it to the correct place and although the screen did initialize (changed from white to black), it didn't display properly. I still need to check that the connections are proper and that there aren't any other shorts in my soldering job. If that checks out, I can try running the init script for the display, but I don't suspect that will do anything. It could be a similar issue as well on another wire.

I am so close now with getting the LCD working with the Pi Zero. I got the desoldering tools in the mail, so I went ahead and desoldered the parts I wanted and cut the board down. Unfortunately while doing so, I broke off a few pads. So the next step was looking at a schematic and figuring out which connections needed to be connected between the Pi and the LCD. I meticulously added wire and did repairs on it and tested each with a multimeter and then soldered wire between the Pi and the LCD.

I then went ahead and downloaded a more recent version of Raspbian and installed it on an SD card, hook...

I have made a bunch of progress. First I'll start with the calculator project. I received the PowerBoost and the battery in the mail, so that allows me to know how well stuff will fit. I started desoldering the connections on the LCD board, but that was soldered way too well, so I ordered a solder sucker and that should help with removing the main connector. I then took the insides of the TI-83 and placed them into the TI-86 case which was kind of a fun project in itself. It involved a little cutting, drilling, and soldering, but in the end it functions well. The only thing is that the labels ...

Well, for now I'm giving up on my 3D printer and moving onto a new project. After the new project is finished, I may circle back to the 3D printer. The new project involves putting a Raspberry Pi Zero W and LCD into a TI Calculator case and getting the buttons to function as a keyboard. I will also be adding a Lithium Ion battery so that the whole thing is rechargeable.

This is something I've had on the back shelf since December or so when I got the idea. In the mean time I've acquired a couple of TI calculators and the Raspberry Pi Zero W. I also got an extension cable and have been planning ...