*********************************************************************** This document was originally posted on the italian Amiga Fidonet areas. It is on Internet by written permission of the author. This is one of the many contributions the Italian community gives to the Amiga users. *********************************************************************** The following document is Freeware, meaning that you can use it and distribute it freely as long as no part of this document is changed. Orginal document by Francesco Ronchi Translation to english by Federico Chiesa To contact the author or the translator check the addresses at the end of this doc. *************************************************************************** Note: remember this document was Made in Italy. Thank the italian Amiga community for this nice little trick. Give credit to the ones who earn it. *************************************************************************** NOTE: We are not responsible IN ANY WAY for any damage caused by (improper) use of the following document. If you don't know what you are doing, don't go on reading. If you do things the wrong way, you have a high chance that you will burn your monitor off. We are not responsible for that. Usage of this document and the information herein is all at your own risk. Note : we have been successfully using this trick for more than 1 year and it has given us no problem whatsoever, even with old monitors. However this was tested (directly by us) only on >1991 C= 1084S monitors. It should work just the same on older models like the 1084 and the Philips CMM8833 (or whatever that monitor is called). Many other people tried it and it has given them no problem, but in case you burn up your monitor, hey, that's your problem. *************************************************************************** What you need is the following: - Commodore 1084 or similar monitor (see below for details) - AGA or ECS chipsets - WB3.0 or maybe 2.1 - No hardware hack/change - Your favourite filezapper Ok. Now: 1. Copy the Euro36 monitor driver to DEVS:Monitors. This monitor handles 73Hz-15Khz screens that *can* *be* *displayed* by the above mentioned monitor (at least our do 8) but not very well because part of the screen is not visible. So you have to: 2. Edit the Euro36 tooltypes to bring down the frequency to about 70-71hz. Trying some values with MonEd I reached for the optimal value (for my monitor) which is: TOTROWS = 0xdd (any other tooltypes should be left untouched). This is not enough, though, because the screen has the right size, but it's too 'high up'. Unfortunately the 'Overscan' program won't lower it, so you have to: 3. Reset so that the system recognizes the new monitor 4. Load the overscan prefs and save them the way they are already. (do not skip this part!) 5. Manually edit the overscan.prefs file in the prefs/Env-Archive/sys/ drawer with your favourite filezapper, and change the value $10 to $15 at offset $039 (this only if the Euro36 is the first in the list in the overscan prefs, otherwise the offset will be a different one). Now, if everything went right, you should have in your screen mode requester the Euro36 mode. Load the Screenmode pref and look at the values of the frequencies. They shouldbe 71hz and 15.64khz in a maximum resolution of 1280x400. Try to select it and hope... NOTE: You are risking to melt down your monitor, so if something looks wrong, turn the monitor off immediately ! (you are advised) Advantages of this method: - A 71hz interlaced screen flickers way less even than an NTSC one (try it with Imagine !) - Appartently the DMA is not slowed down by it (unlike the DBLPAL 8(, and some times it even looks like the refresh is faster) Disadvantages: - The screen height is limited to 400 pixels, like in NTSC. - Only horizontal overscan is possible. I have no idea on which monitors this trick will work on, but on my 1084S it works great since last year, even if the manual says it is only 50hz. This trick *DOES* *NOT* work on TVs (no way, don't even try) but it should work on other similar monitors that support NTSC. Let me know about it. *********************************************************************** This document was originally posted on the italian Amiga Fidonet areas. It is on Internet by written permission of the author. This is one of the many contributions the Italian community gives to the Amiga users. *********************************************************************** All the info you need is here. Please don't send messages unless really necessary. Thanx are appreciated though 8') However, if you are successful in using this trick, please send us a message specifying your monitor bran, model, and year of production, so we can include it in future releases of this document. Fidonet : 2:334/21.45 Francesco Ronchi ( author ) 2:332/516.7 Federico Chiesa (translator) Internet : so98@delta0.lica.unimo.it (translator) until summer 95