#Amethyst is a type of #quartz, crystalline #silicon dioxide (#SiO2), which contains inclusions of #iron on the #crystal.
This #MacroPhotograph of an amethyst specimen shows the seemingly-chaotic crystal growth.
#Macro, #Photograph, #Photography, #Photo, #Mineral, #SiliconDioxide, #AmethystCrystal
Buy a print: https://heronfox.pixels.com/featured/amethyst-specimen-1-heron-and-fox.html

Sculture di quasicristallo modellato dalla forza dei fulmini. Folgorite e quasicristalli, la nuova rarissima specie chimica. La folgorite, come suggerisce il nome stesso, è un ammasso vetroso generato da una folgore. È un fenomeno incredibilmente affascinante che modella delle vere e proprie sculture similari a dei fulmini.
#ammassovetroso #Folgore #Folgorite #fulmine #fulminepietrificato #NebraskaSandhills #quasicristallo #SiO2 #universome

https://scienzamagia.eu/scienza-tecnologia/sculture-di-quasicristallo-modellato-dalla-forza-dei-fulmini/

A #macro #photograph of an #amethyst #crystal merging into its #rock #matrix. The #deep #purple merges into a #yellow layer, a #white layer, and ending in #green rock. Amethyst is a kind of #quartz, which is crystallized #SiliconDioxide #SiO2 that is colored purple by #IronOxide #inclusions in and on the crystal. This #dramatic change in color took place over an extremely long time.
https://heronfox.pixels.com/featured/amethyst-specimen-6-heron-and-fox.html

A #macrophotography #photo of a bunch of small #carnelian #crystals in an #antique #glass #jam #jar. Carnelian is a form of #chalcedony colored by #IronOxide #inclusions, usually hydrous, and ranging from submicroscopic to microscopic in size.
Chalcedony itself is another form of #SiliconDioxide, #SiO2, in a #cryptocrystalline form. Its crystal structure is made of many small crystals whose structure is only visible under a microscope.
Despite have the same #ChemicalFormula, #Quartz and chalcedony look wildly different from each other.
What kinds of “#gems” await in places where #WaterIce is harder than rock?’
The jam jar is also SiO2 in a different state. How versatile is CO2? Can you keep jam in it?
https://heronfox.pixels.com/featured/small-carnelian-specimens-in-a-glass-1-heron-and-fox.html

A #macrophotography #photo of a #quartz #crystal and the #rock matrix it started to grow on. Projections and partial #terminations, as well as rock #inclusions give character and color to the otherwise milky #translucence or #transparent #color of pure #silicondioxide #SiO2.
It’s #interesting (to 🦊 Fox, the #photographer) that SiO2 is a clear analog of #carbondioxide #CO2. #Silicon and #carbon are both in the same #Group on the #PeriodicTable (#IUPAC #Group14 to physicists, #GroupIV). But on the #Earth, SiO2 #crystallizes. Under what #conditions does CO2 crystallize? What do CO2 crystals that have grown over #geologictime look like?
Sometimes 🦊 wonders odd things.
https://heronfox.pixels.com/featured/quartz-crystal-specimen-3-heron-and-fox.html

@kianryan one *very* useful hint for getting the proper #CPM #Overlay for a #rc2014 SIO serial setup is looking for a "Big Board II" overlay. It used to have the same #CTC and #SIO2 chip, so you just need to adapt it to your port addresses and maybe the initialization for the SIO clock divider. Saves a lot of time!

Here's this week's sunday afternoon project:

today I've been tinkering with a cheap #QR203 #ThermalPrinter (used by many chash registers) connected to #SIO2 port B of my #rc2014 - so now I have a cheap printing option for my little #Z80 fellow.

Using "DEVICE LST:=COM1" on my CP/M ( #RomWBW version ) I was immediately able to use the CP/M CTRL-P shortcut to print all input and output directly to the printer as well.

After some digging on the web, I actually found the proper Manual for the #EscapeSequences used by the printer here ("Printer Programmer Manual"):

http://www.cnfujun.com/en/init.php/service/manual

P.S.: my tinkering was inspired by this article on hackaday.io

https://hackaday.io/project/177988-68k-mbc-a-3-ics-68008-homebrew-computer/log/195649-using-a-small-thermal-printer

@jskists @rc2014 @Raspberry_Pi a few days ago, @lyuba posted some cool #ESP8266 code, maybe one could adapt that. But it would require the #ESP to be flashed for just that particular use, though -> https://github.com/ringtailsoftware/lyuba

Or you add another #SIO2 connected to another #ESP for just that purpose ...

I'm currently back at tinkering with my #rc2014 setup since the machine is rather accessible when it comes to understanding how the individual hardware components, in my case the #SIO2 chip, have to be set-up for proper use with your own #assembler code.

This also leads to the inevitable use of some 45 year old documentation on the topic and I am still impressed by the very clear, structured and comprehensible work Zilog provided!

Just take the snippet I took off the SIO/2 write register documentation. I'm the visual/hands-on learning type of person and the screenshot of pg. 30 from the "Zilog Z80-SIO Technical Manual" feels so natural to me. One look and you know what function a certain bit in a certain register serves.

Also, the technical explanations in the manual are written by engineers who wanted to convey technical information in an easy and understandable way and who did not succumb to academic elitism in writing.

#zilog
#z80
#sio2
#manuals

... and my #sio2 polling code is finally working! Yay!!

#rc2014
#z80
#assembler
#codinforfunandknowledge

I get the distinct feeling, that using IM2 is not the way to go for what I want to accomplish:

"With INTERRUPTS, the CPU ignores the SIO until it's attention is grabbed by the SIO raising an INTERRUPT. In the case of the much simpler POLLING method, the CPU periodically shuffles over to the SIO to see if it has anything that needs dealing with. Both can be made to work equally well, but from the programmer's point of view, it is often far easier to resort to polling."

https://www.izabella.tk/html/z80_sio_programming_hints.html

#z80
#zilog
#sio2
#assembler