BillO wrote:
Nice compact module!
Thank you!
AndrewP wrote:
It was your video on building a HEX display that inspired me to build one for myself, big thanks for that!
Glad to hear it! I've been trying to complete my breakout board PCB in the main 65C816 series but I plan on making a Hex Display episode in the next couple weeks.
GARTHWILSON wrote:
AndrewP wrote:
Ultimately I'd like to use the
ATF16V8BQL-15XU because it's only 6.6mm x 4.5mm and would fit on the back of the surface mount Kingbright displays I'm using (along with the '555). If anyone manages to get a dual hex display going with a '16V8 that'd be awesome but it's not a tangent I want to go off on as I'm already, like, three major tangents deep
I would use a microcontroller, a single IC. In fact, I started such a project 3½ years ago, then it got put on the back burner, and now I don't even remember why. I have several other projects going though, so it'll have to wait. I may still complete it later and offer it if someone else doesn't offer one.Yeah, I went the MCU route for a few reasons:
- it can be programmed after assembly, unlike the ATF SPLDs, so I can outsource assembly to a site like JLCPCB, and thus make use of 0201 components to make it fit under the display
- I don't need special hardware to program it (like SSOP ZIF sockets...)
- it has a built-in oscillator for easy display multiplexing
- it can be programmed with well known, available tools like the Arduino IDE
One issue is the speed of interrupts prevents the implementation of a register in a reasonably fast circuit (one clock cycle of the MCU is 125ns, of which you need a few to interrupt and read the pins...).
If you need latching of the value, you need an actual logic IC in front to do it quick enough. I managed to fit an ATmega MCU + a 74LS573 latch under the display recently, but I have yet to order this one.
Someone suggested using a PIC microcontroller's configurable logic cells to achieve the speed needed in a single IC, but I haven't tried it yet. You can only map 8 pins to the cells' inputs but you need 9 with the latching signal.
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