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@@ -10,7 +10,7 @@ This damage can sometimes be repaired trivially, but many times it requires a lo
There are other projects with the same goal out there, but none of them is Open Source and none of them comes with both schematics and board. This is a big advantage, since anyone can modify the board and make new improved versions, as long as they release their modifications it with the same license. I have come up with [some ideas for improvements](https://github.com/SukkoPera/Raemixx500/issues/14), feel free to help :).
The first version of the board was released in April 2020 as untested, in the hope that someone from the Amiga "Community" would jump in and help with the testing. Well, that took quite some time but in the end someone finally understood that Open Hardware is about trying to do your part rather than coming up with [heaps of useless talking and moaning](https://news.ycombinator.com/item?id=22887349) or [blatant stealing](https://retrotechlyfe.com/home/ols/products/commodore-amiga-500-computer-motherboard-logic-board-premium-gold-immersed-traces-stellar-signal-integrity) and allowed this project to reach the next milestone. So despite knowing he could be jumping into the void, fellow Italian living in Japan Edoardo Auteri put confidence, money, time and effort into assembling a board and testing it thoroughly. While he was at it, he came up with some interesting ideas which ultimately encouraged me to make Version 2, which fully passed all tests. You can read more about the development and testing of the board on [the official development blog](https://hackaday.io/project/180442-rmixx500-amiga-500-mainboard).
The first version of the board was released in April 2020 as untested, in the hope that someone from the Amiga "Community" would jump in and help with the testing. Well, that took quite some time but in the end someone finally understood that Open Hardware is about trying to do your part rather than coming up with [heaps of useless talking and moaning](https://news.ycombinator.com/item?id=22887349) or [blatant stealing](https://retrotechlyfe.com/home/ols/products/commodore-amiga-500-computer-motherboard-logic-board-premium-gold-immersed-traces-stellar-signal-integrity) and allowed this project to reach the next milestone. So despite knowing he could be jumping into the void, fellow Italian living in Japan Edoardo Auteri put confidence, money, time and effort into assembling a board and testing it thoroughly. While he was at it, he came up with some interesting ideas which ultimately encouraged me to make Version 2, which **fully passed all tests**. You can read more about the development and testing of the board on [the official development blog](https://hackaday.io/project/180442-rmixx500-amiga-500-mainboard).
## Differences from original
The initial objective was to come up with a new mainboard as similar to the original one as possible, while including minor modifications that would improve its usability. This mainboard was designed with *reasonable* - not *maniacal* - accuracy to the original design. Most care was taken in the positioning of components that ought to be in a certain position (i.e.: screw holes and I/O connectors), to ensure drop-in replaceability. Other components and tracks are "more or less" there, but as the board was wholly laid out from scratch by hand, don't expect sub-millimeter accuracy.
@@ -55,7 +55,7 @@ Some modifications were soon added in, in the hope that they would be useful. Le
**Please be careful**, as getting the wiring wrong after you have resoldered LF1/LF99 back in place can definitely damage a lot of the components of the A500 you have just built.
By the way, if you are looking for a suitable power supply, I'd recommend getting a Meanwell RT-65B or RBT-60B (FIXME).
By the way, if you are looking for a suitable power supply, the [Meanwell RT-65B](https://www.meanwell.com/webapp/product/search.aspx?prod=RT-65) or [RPT-60B](https://www.meanwell.com/webapp/product/search.aspx?prod=RPT-60) are popular choices.
* **Kickstart Switcher**: This is a set of jumpers that will allow you to store more than one Kickstart image on a single ROM chip and enable one at will. If you want to use it, start by locating jumpers J91-93, which sit right above the ROM socket and are shaped like a Tetris piece. If you haven't touched them yet, each of them will have a horizontal trace connecting the two middle pins (this position is marked as *DIR* on the silkscren, standing for *DIRect Connection*). You will need to cut all the three of these traces, the suggested place for the cut is marked with a vertical white line. Use a multimeter in Continuity Check Mode to make sure the connection is really interrupted and solder pin headers to all pins. Now you can place jumper caps vertically to force the ROM to see the A18-A20 lines as permanently high or low, which will allow you to select one among different slots as follows:
* 256k Slots