Currently, the under-development (not by me, I hasten to add) eZ80 version for the Agon Light doesn't do that, it initialises PAGE to &46842, so I've created an Issue at GitHub about it. I'd like some reassurance (or otherwise) that it's a reasonable request, and that the expectation of PAGE being on a page boundary isn't something I've imagined.
Should PAGE always be page-aligned?
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Richard Russell
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- Joined: Tue 18 Jun 2024, 09:32
Should PAGE always be page-aligned?
Every version of BBC BASIC that I am familiar with initialises PAGE to a 'page boundary', i.e. an address &xxxxxx00. It is, after all, the origin of the keyword PAGE itself, so a non-page-aligned value of PAGE is something of a contradiction, even if in modern versions of BBC BASIC it's not actually a requirement.
Currently, the under-development (not by me, I hasten to add) eZ80 version for the Agon Light doesn't do that, it initialises PAGE to &46842, so I've created an Issue at GitHub about it. I'd like some reassurance (or otherwise) that it's a reasonable request, and that the expectation of PAGE being on a page boundary isn't something I've imagined.
Currently, the under-development (not by me, I hasten to add) eZ80 version for the Agon Light doesn't do that, it initialises PAGE to &46842, so I've created an Issue at GitHub about it. I'd like some reassurance (or otherwise) that it's a reasonable request, and that the expectation of PAGE being on a page boundary isn't something I've imagined.
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jgharston
- Posts: 56
- Joined: Thu 05 Apr 2018, 14:08
Re: Should PAGE always be page-aligned?
I think it's a reasonable request. ARM BASIC has PAGE at &xxxx00, and I had to check to remind myself, PDP BASIC also has PAGE at &xx00. I went through some careful tweeking of the workspace below PAGE to ensure everything was &00xx aligned, even though - like Z80 BASIC - the workspace simply runs on after the code and could be just whatever address the workspace after the code happens to end at.Richard Russell wrote: ↑Thu 23 Apr 2026, 16:42 Every version of BBC BASIC that I am familiar with initialises PAGE to a 'page boundary', i.e. an address &xxxxxx00. It is, after all, the origin of the keyword PAGE itself, so a non-page-aligned value of PAGE is something of a contradiction, even if in modern versions of BBC BASIC it's not actually a requirement.![]()
Currently, the under-development (not by me, I hasten to add) eZ80 version for the Agon Light doesn't do that, it initialises PAGE to &46842, so I've created an Issue at GitHub about it. I'd like some reassurance (or otherwise) that it's a reasonable request, and that the expectation of PAGE being on a page boundary isn't something I've imagined.![]()
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jgharston
- Posts: 56
- Joined: Thu 05 Apr 2018, 14:08
Re: Should PAGE always be page-aligned?
Incidently, where/which eZ80 port to Agon Light on GitHub? From searching I've found several repositories all not updated in several years, and some also non-updated repositories on other sites, and none with comments less than a couple of years old.
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Richard Russell
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- Joined: Tue 18 Jun 2024, 09:32