MC6800

the CPU. the motorola MC6800. once quite popular, but somehow overlooked a little, imho, with the retro computing revivial of the 2010s. it runs lots of operating systems, like CP/M, FLEX, and more.

this is the original chip that the 6502 team decided to try and radically simplify with their design. they were right. the 6502 reigned supreme.

MC6875

this is the 6800's external clocking logic. if you csn get one, your life will be easy. it will do all the clocking really well. this is an exotic chip now, however. ngl, at the price i got this, i will be hoarding them.

this fits into the main cpu subcircuitry. we just need to get some passive components and then a 4 MHz crystal.

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DMA Video Logic

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these two lil buddies are the CD4014, and CD4040, respectively.

they do the main clocking and signalling for the composite out video.

the 4014 is a parallel in serial out shift register or buffer register. then the 4040 is a binary counter. you get the idea.

please refer to the DREAM6800 schematics.

these chips allow us to do DMA graphics @ 64 columns by 32 rows as a dot matrix.

256 bytes of RAM in the DREAM's memory map are simply pixels in RAM

Miscellaneous

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1. a now very exotic LM566. not a 555 it's a really interesting VCO. voltage controlled oscillator. not surprising, it's from the digital audio in ciruitry. HAM lovers watch this space.

3. 10 x LM741s, lil cuties. they're ancient now.

4. the power ICs.