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XVI and changing the bios

Started by hyperneogeo, September 11, 2015, 03:16:11 PM

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hyperneogeo

Now I know for an XVI you need the CZ-6BE2A memory board to change the bios. My question is, how do you set it so the computer will know to boot from that bios? Is it that jumper switch on the CZ-6BE2A? Or do I have to set it in switch?


eidis

 Hi Hyperneogeo !

Have not personally tried this so please take the following information with a grain of salt. Judging by the looks of before mentioned RAM board, it looks like all you have to do is write the IPL to eeproms and move the jumper on CZ-6BE2A to position 2,3. The same jumper is present on my ACE-HD motherboard near the eeprom sockets as well and set to the default position just like on the CZ-6BE2A.

ACE HD motherboard
http://content5-foto.inbox.lv/albums/e/eidis/X68000/Top.jpg

CZ-6BE2A - Memory expansion board
http://gamesx.com/wiki/lib/exe/detail.php?id=x68000%3Acz-6be2a_-_memory_expansion_board&media=x68000:cz-6be2a_4.jpg

Now comes the fun part. How to burn the eeprom. You will most likely need two W27C512 Eeprom chips which have a speed of 45ns or, if the X68000 is very picky, the classic 27C512 Eprom which is much slower. Eeprom chips can be electronically erased, however the Eprom chips will need a UV lamp in order to be erased. Step two would involve taking an IPL of your choice (128kb) and splitting it to ODD and EVEN files. You will get two 64kb files. The third step will be trial and error. I have tried it with Commodore 64 but never with an X68000 so you will have to experiment a bit. According to the X68000 memory map, the IPL starts at 0xFE0000 so this is the offset which you have to enter before writing data to both chips.

X680x0 Memory Map
http://gamesx.com/wiki/doku.php?id=x68000:memory_map

Try it and please post your results. This could make a great Wiki article.

Keep the scene alive !
Eidis
X68000 personal computer is called, "X68K" or "no good good" is called, is the PC that are loved by many people today.

hyperneogeo

Quote from: eidis on September 22, 2015, 02:21:22 PM
Hi Hyperneogeo !

Have not personally tried this so please take the following information with a grain of salt. Judging by the looks of before mentioned RAM board, it looks like all you have to do is write the IPL to eeproms and move the jumper on CZ-6BE2A to position 2,3. The same jumper is present on my ACE-HD motherboard near the eeprom sockets as well and set to the default position just like on the CZ-6BE2A.

ACE HD motherboard
http://content5-foto.inbox.lv/albums/e/eidis/X68000/Top.jpg

CZ-6BE2A - Memory expansion board
http://gamesx.com/wiki/lib/exe/detail.php?id=x68000%3Acz-6be2a_-_memory_expansion_board&media=x68000:cz-6be2a_4.jpg

Now comes the fun part. How to burn the eeprom. You will most likely need two W27C512 Eeprom chips which have a speed of 45ns or, if the X68000 is very picky, the classic 27C512 Eprom which is much slower. Eeprom chips can be electronically erased, however the Eprom chips will need a UV lamp in order to be erased. Step two would involve taking an IPL of your choice (128kb) and splitting it to ODD and EVEN files. You will get two 64kb files. The third step will be trial and error. I have tried it with Commodore 64 but never with an X68000 so you will have to experiment a bit. According to the X68000 memory map, the IPL starts at 0xFE0000 so this is the offset which you have to enter before writing data to both chips.

X680x0 Memory Map
http://gamesx.com/wiki/doku.php?id=x68000:memory_map

Try it and please post your results. This could make a great Wiki article.

Keep the scene alive !
Eidis

Thanks for the information. I'll try it out in a few days.  Tho, I looked in switch.x and it says an option for Boot : ROM....does this have to be selected as well?