Sinclair ZX80 / ZX81 / Z88 Forums

It may be found in the zip here:
http://forum.tlienhard.com/phpBB3/viewt ... ter#p24965

Per design, the Z condition bit is not affected by ADD HL,BC...

Apparently z80asm doesn't know this undocumented instruction... For example zasm and sjasm do handle it:

https://k1.spdns.de/Develop/Projects/zasm/
http://www.xl2s.tk/

The attachment on the previous page with ZTOS.P is updated to do the startup as described in the previous post, and I think it is indeed solved

On my ZXmore with ZXmaster 1.7 (but both when switched on and off), and an early CPLD, I do get the inverted screen. Without line 400, it is not inverted. The RAND indeed modifies the dummy display file according to the manual on page 12.

Does the attached demo run ok? I changed a few calls to the ROM...

Yes, it is a special version (with a tiny patch for the tape loading) of the latest Sponzy I obtained from Zsolt.

siggi wrote: ↑Tue Oct 09, 2018 9:14 am PS: Instance 1 may also be a ZX81x2m.rom? Correct?

Correct!

Attached is a ZX81 program to start Sponzy2018, so that TAPs such as FLIPPIT can be loaded via USB on the ZXmore. Have a ZX81 at instance 1, and program the Sponzy in the Flash ROM at instance 2. Start instance 1, and LOAD ZTOS.P with DS-L. Next, Sponzy should start automatically, and has access to ...

Congratulations!!!