mgolombeck / dolores Goto Github PK

Hi! I originally found your DOLORES library at your web site:

http://www.golombeck.eu/index.php?id=48&L=1

Not seeing any mention of a repository or a preferred way to report bugs to you, I contacted you by email using the contact form on your web site.

I now found this GitHub repository and see that it is in fact mentioned on your web site but only as a line item within the "Former STABLE release" section:

• Find the source code for the base library on GitHub (released under GNU gpl3).

I hadn't initially paid attention to the "Former STABLE release" section since I saw no reason why I wouldn't want to use the latest stable version.

I think it would be a good idea to move the reference to the GitHub repository out of the "Former STABLE release" section and up into one of the first few paragraphs on the page to make it more likely to be seen by everyone.

I contacted you about this by email already but now that I've found that you have this GitHub project I wanted to file it here too to aid you in tracking it.

On your web site it says:

From the Apple //e enhanced onwards a double LORES mode with 80 x 48 pixels in 16 colors is available.

This message is repeated in the about screen of the dolores disk.

This statement is misleading because in fact the double low-res mode is available on unenhanced Apple //e computers as well, provided that they have a revision B logic board. Revision A logic boards were only used for the first several months of Apple //e production in early 1983; revision B logic boards were used from then on. Apple offered free logic board exchanges for revision A logic board owners for many years (I got mine in mid 1989) so I would guess that the vast majority of unenhanced Apple //e computers support double low-res graphics.

However your library does not support unenhanced Apple //e computers unless they have been upgraded with a 65C02 processor. You indicated by email that you intentionally use 65C02 opcodes for performance reasons which is understandable, though it is unfortunate that there were probably at least 1½ million unenhanced Apple //e computers made (which may be ⅓ of all Apple //e computers made) that would be able to run software made with your library were it not for the 65C02 requirement.

It would be a good idea to reword the web site to clarify that the requirement is a 65C02 processor, not the other enhancements of an enhanced Apple //e, and that this is a requirement imposed by your library, not by double low-res graphics mode.

The wording of the message in the readme of this project is a bit clearer.

So that users with 6502 Apple //e computers who don't read the documentation carefully are not confused, you might want to enhance the demo program so that it detects the processor and if a 65C02 is not found, it displays an error message to that effect. You should do something similar if the user is on an Apple II or II Plus since conceivably an Apple II or II Plus owner could upgrade to a 65C02 but that would not give them double resolution graphics modes. I found you've already documented how to do Apple II system and processor detection on your web site. If there's a way to identify a revision B logic board in software that would be a nice addition as well.

I see that you've licensed this library under the GNU General Public License. My understanding of this license is that if a program or another library wishes to use a GPL'd library, then that program or other library must also be released under the GPL. You may want to spell this requirement out specifically in your readme and on your web site so that potential users of your library who may not be totally familiar with the implications of the GPL will be fully aware of the restrictions that will be imposed on them with regard to what license they may choose for their own software.

If it was not your intention to impose these restrictions on your users, you might consider relicensing your library under the GNU Lesser General Public License which will give your library's users the freedom to choose whatever license they prefer for their own software.

You suggested by email that I could use your library on my unenhanced Apple //e by upgrading its processor to a 65C02 (#2). There are two bugs in the demo program selection screen of your HELLO program that affect unenhanced Apple //e computers as shown in this screenshot:

1. The title is on the left instead of centered. This happens because there seems to be a problem with the first output after initializing the 80 column card. It can be avoided by changing line 420 from PRINT : PRINT D$;"PR#3" to PRINT : PRINT D$;"PR#3" : PRINT.
2. The second column of demos overprints the first. This happens because you use HTAB with a value greater than 39. Instead of HTAB n when n is greater than 39, use POKE 1403,n-1, twice on line 470 and once on line 490.