The original rocket's primary display was 4 rows of 7-segment LEDs. It was actually just 4 of our 1-row boards all stacked on top of each other. For the makeover we replaced it with a native board that had 6 rows:
The old display boards were controlled by bit-banging latches over long parallel cables. This turns out to be a very bad idea (any EE could tell you this, but we're computer scientists). In the 2019 update we changed the remote display control from bit-banging to proper networking using I2C-based packets. We didn't want to remake every single display board, so we came up with a shortcut: we designed little snap-on "dongles" that speak the new I2C protocol and translate to bitbang commands that just go a few cm to the display board below. Here's the dongle installed on one display board:
Here are some of our end users enjoying our efforts:
https://photos.app.goo.gl/8zca5kXXbAf2vcJh6
Here's disco mode, though I think this is with the old audio synthesizer:
https://photos.app.goo.gl/vkenYZKATyDRB1386
The original rocket's primary display was 4 rows of 7-segment LEDs. It was actually just 4 of our 1-row boards all stacked on top of each other. For the makeover we replaced it with a native board that had 6 rows:
https://photos.app.goo.gl/Dtiv5dN8FfrBAkDK7
Here's a video of it playing pong on my bench before installation:
https://photos.app.goo.gl/bWfQkTaF3eUyacb78
The old display boards were controlled by bit-banging latches over long parallel cables. This turns out to be a very bad idea (any EE could tell you this, but we're computer scientists). In the 2019 update we changed the remote display control from bit-banging to proper networking using I2C-based packets. We didn't want to remake every single display board, so we came up with a shortcut: we designed little snap-on "dongles" that speak the new I2C protocol and translate to bitbang commands that just go a few cm to the display board below. Here's the dongle installed on one display board:
https://photos.app.goo.gl/z9e6z6p4vXgb5j5aA
Here's a side view showing how they stack:
https://photos.app.goo.gl/tAzF4Aeq1dWVHFxE6
And here is one of the new dongles in situ with the new STM32-based primary controller, and the upgraded 32-bit audio synthesizer:
https://photos.app.goo.gl/oQxEZKRUZsK4Ry6W7
We're both pilots so of course we had to put in a Hobbs meter. The rocket has over 600 hours on it:
https://photos.app.goo.gl/ydecF3q8VkdnJB1JA