If you read the last post carefully you might have stumbled over “Tailgunner” on the latest VecFever firmware.
This is the newest “programming wizardry” of Thomas with his VecFever hardware.
Yea, but actually this time credits do no go to Thomas alone – a couple of other people were involved (see also the credits in the Tailgunner Video accomanying this blog entry) namely:
– VTK some sounds
– and especially: Graham Toal and his involvement in the static binary compilation
– ‘original cinematronics emulation group’ : Neil Bradley, Jeff Mitchel, Zonn Moore
Static Binary Compilation (SBC)
For a “thorough” explanation see google or one link in special: http://www.gtoal.com/sbt/.
Graham also pursues a very similar project, using a Raspberry Pi Zero W connected to the cartridge port of the vectrex, a recent video of his can be seen at: https://www.youtube.com/watch?v=Y5aSu_qoek4.
Actually Graham has been in close contact with Thomas and “sparked his interest” and is thus kind of responsible for the VecFever implementation.
My personal short explanation of sbc:
The (original) binary of a program is translated to a “gigantic” switch … case statement (in C or actually any other language). Each “case” being an address at which the original binary had executable code. Each “case” than semantically does the same as the code at that address. I/O behaviour uses special “hooks” (subroutine calls) which are implemented independendly.
The state of a thus “emulated” machine is also kept in apropriate data structures (registers of the processor…).
What if boils down to in the end…
Thomas compiled the SBC of Tailgunner for the processor the VecFever uses, he implemented the “hooks” for the Vectrex and optimized the hell out of it.
The result is – there is now a standalone emulator of the original Tailgunner running on the VecFever which uses the Vectrex as its output device. It runs at the original speed and the screen update the vectrex does is also (more than) original.
A VecFever now plays the original TailGunner.
A “tiny” drawback – the sound is not original – and the sound is also still being worked on (by Thomas and VTK – no wonder I do not hear anything from Ollie 🙂 ).
If I understand Thomas right – Tailgunner working on the VecFever is only a “by product” of him trying this stunt on a seperate dedicated Tailgunner cartridge – something like:
Ok last thing – a video playing the tailgunner…
(at the beginning I let the scroll text of the credits and info display in all length… there is actually a tiny little gameplay at the end!)