FIXED! ZX Harlequin Update 2 

Optional for joystick interface could mean "it's optional if you have the joystick interface (and not if you don't)" or "it's optional, it's only for the joystick interface" ;-)

Glad to see you finally got it working! Certainly doesn't help when the instructions aren't quite right.

Glad to hear it is sorted . Happy birthday !

Great job, happy birthday, and happy new year! Hope 2024 is amazing

Happy birthday and a happy new year. Like your stuff

Happy birthday and a happy new year to you and all your family Lee.

Happy birthday Lee. 🥳🍾🍾🎉

Happy birthday 😄👍

Happy birthday and happy new year from Hungary! The pins on the DIP switch are labelled X16..X18 and the top 3 resistors in the array have the same labels (called network names on schematics), so they are connected. You can use a shorter (4 pin) resistor array with the common and the three top resistors if you'll never connect the joystick.

Happy birthday and happy new year, Lee! 🎉

Thanks for the very interesting video series and the solution. But the sound of the video is too quiet for me, is there anything that can be changed? Happy New Year!

Happy birthday Lee, and happy New Year to you also. I look forward to more great videos from you in the near future.

I'm glad you got it working Lee :) I'm glad I just installed everything now lol. Happy new year! and I hope you had a good birthday :)...

Nice to see that you've sorted it. Nice bit of kit. It's a speccy after all, what's NOT to like? Happy New Year!

As others have said, the schematic does show the pull-up resistor connected to the DIP switch implicitly by net-name. ....which isn't a technique I particularly like, because if you don't spot the net name on some apparently random part located somewhere else on the schematic then you miss the connection. At least in this instance the dip switches and pull-up resistor pack are located alongside each other on the schematic - in which case there isn't really any reason not to connect via net lines to make the link really obvious. If three net lines are likely to get messy crossing over each other then draw a short bus containing those three nets so there's only a single line going between the portions. As shown I'd just say it isn't a very well drawn schematic. Using KiCAD's 'global label' symbols on the inter-connected nets at least makes it clear the nets are linking elsewhere within the design rather than leaving the pins floating as shown. The clear note about the part being optional when it obviously isn't is also pretty poor design documentation.

Does seem like the instructions are wrong - the schematic shows pins 2-4 of R61 connected to X16-X18 of the dip switch and acting as a pull up resistor. (I found the schematic by searching the internet) To be fair - the instructions from what I see shown on the video are fantastic (like everything else I’ve seen from Byte Delight) - but need a slight tweak Happy Birthday

Well that sucks I missed another live one.

That's interesting! I don't have the parts marked as optional installed on my Harlequin 128 from Bytedelight. I don't need switchable ROMs. I only have an EPROM with just the Spectrum 128 ROM in it. And it is working flawlessly for years now. Does this only affect systems with a larger EPROM / EEPROM chip?

I would’ve fixed it in two seconds with Chewed gum Curry powder KitKat rappers And big aubergine