Sinclair ZX80 / ZX81 / Z88 Forums

I should have noted, that this used no commercial joystick, but microswitches connected to the lines for the cursor keys.

Thanks for trying it out. I wasn't aware that this is no official Zilog instruction. It seems that I have to consider another assembler then or stick to the mundane, something like

Is there a ROM which enables the Spectrum to run ZX80 BASIC programs, whether it be an interpreter or a compiler? I'm searching for something like this https://www.sinclairzxworld.com/viewtopic.php?f=5&t=465 , but the other way round. Especially I'm hoping that this might enhance the speed, of progr...

I once had such a thing with at least 1 meter of cable and a connector on the 81. I may have been quite naive, but it worked.

I want to use one of the shift left logical directives. According to the headline here http://z80-heaven.wikidot.com/instructions-set:sll they can either be written SLL or SL1. However the table shows sla directives, which do work as expected. But I have no success with using SLL instead.. The progr...