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Dear All, after I was sleeping two days over opening a thread on "an idea", I am just doing it: This thread is intended to be a (Mindful) Pub to discuss ideas/projects/wild thinking/just memories/the good ol'days/8 bit/crazy16bit/express printers printing NCC1701/PDP10/11 ... and mostly 8bit computers - controlling LEGO 4.5V/9V/12V/RC/PF/ and yes: PUp devices. Whatever comes to mind. 8bit computers are OLD. Very old. As in: You may think the chemist down the road is old, but that's just peanuts to the age of 8bit computers. We are talking true retro here. C64, Dragon 32, Oric-1, BBC Micro, ZX's, Amstrad CPCs and so on and so forth. I don't know why, but it just never "left" me. When I was 23 years old, my wife (I was studying - well - chemistry) allowed me to buy a Sinclair ZX Spectrum. And it all began. Games never ever interested me (other than cracking the "copy protection" using the disassembled machine code) - it was the hardware. And changing/adding things. Controlling periphery. I graduated with a degree in chemistry though - and all figured out is "true homebrew". It was the world of TTL, CMOS, and ECL ... and the world of 16k x 1bit chips being expensive. Just imagine: The 16k ZX Spectrum I had was ready to be upgraded to 48k. There was also a factory version of the 48k Spectrum. To make that one as cheap as possible, Sinclair used defective 64k x 1bit chips: These chips are organized in 2 banks of 32k. Upon final testing manufacturers as TI and others sold chips with one defective bank to other companies as "32k" chips. Can you believe that? Yes of course. It makes total sense! But today? Never ever. Now, the idea for this thread is: Can we control ancient or even current LEGO electronics with 8bit computers? I am working on: Let a ZX Spectrum talk to an RCX brick. Why? Because. Nothing else. It has remotely to do with LEGO bricks being around since the 1960s - and still clutching - and LEGO electronics officially appearing and disappearing even faster than fashion trends do. You may think: So what. He has the ZX IF1 featuring an RS232 port. Well. The ZX speaks (hardwired = bolted in) 1 start, 8 data, no parity, 1 stop bit. The RCX speaks (again: Hardwired into the UART) 1 start, 8 data, odd parity, 1 stop bit (Challenge 1: Parity change). And then: The LEGO IR serial tower cranks out and sucks in bytes with no protocol at blistering 2400 Baud. The ZX IF1 can't handle that: After receiving 1 byte is pulls down the CTS -> RTS line - allowing one more byte and then think about how to store that (Challenge 2: HW protocol - the tower is totally dumb). Possible solution: Arduino as translator. We'll see. This thread will not be heavily populated, I believe. And it will take time. We are talking 1980s. There are some folks here on EB though who may have something to say ... or maybe not. @dr_spock suggested the title of this thread @Duq repairs old washing machines @zephyr1934 knows how to print NCC1701 on endless paper @UltraViolet likes when an EB topic is derailed because of 8bit computing ... This is it. Don't expect a viral thread. I am old. The cool thing though is: Posting here after ... let's say a year or so of silence will not get the moderators mad, as it is designed to be a repository All the best, Thorsten P.S.: Just for those who were born 2000(+) : k stands for kilo. A 16k x 1 RAM is a chip that holds 16384 bit (0/1). You needed 8 to get 16kByte RAM. Today, a 16G x 8bit DDR3 DIMM module, which holds about 1 million times more bytes, sells for about the same price as 16kByte cost in 1982. In other words: 1 bit then was 1.000.000 times more expensive than 1 bit is now, 40 years later.