Displaying a ZX Spectrum loading screen on a Tatung Einstein

Welcome to the Retro Tech Loft, thanks for stopping by, it is much appreciated!
The ZX Spectrum and other popular 8 bit home computers from the early 1980s had a unique way of loading and displaying a loading screen for a program or game.
For a standard screen, compatible with ZX Spectrum, a SCREEN$ file is 6912 bytes. It's just a dump of the screen memory.
The first 6144 bytes store the screen bitmap: 256x192 pixels, 1 bit per pixel (on or off). The layout is not linear.
The screen bitmap is divided horizontally into three thirds: each one is 2048 bytes and store 8 text rows of 32 column each one (each character cell has 8 scans of 8 pixels each one).
For each third, the first scan of each character cell is stored, left to right, top to bottom. Then, the second scan, then the third, until the last one, the eighth. After this, a new third is stored in the same fashion.
This resulted in the screen being displayed line by line 3 sections at a time.
Each byte stored has 8 pixels: the Most Significant bit belongs to the leftmost pixel as shown on the screen.
Following the bitmap region, the remaining 768 bytes store the attributes.
I took this principle and created some code in Z88DK C to display the .SCR file on the Tatung Einstein.
Simple enough, load the .SCR file into a buffer, take each row of 32 characters from the buffer, do some bit shifting and test to see if the particular bit is on. If it is, plot a white pixel on the screen. RInse and repeat until the buffer has been consumed.
The colour and attribute side of things is a bit more tricky on the Einstein, so that will be for another video!
I may also release the C source code to this in the future.
Thanks for watching,
See you all in the video.
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Mike.
** Voice Over generated using AI as a first attempt to re-create missing audio. **
#loadingscreens
#tatungeinstein
#zxspectrum
#retrocomputing