Pablo Sanchez
Retro Member
- Joined
- Aug 31, 2017
- Messages
- 124
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Στο Ultimax mode η ROMH αντικαθιστά τον λειτουργικό πυρήνα kernal στην $E000. H ROML παραλείπεται.
In the “ultimax” modes, the Kernal ROM (0xE000 – 0xFFFF) is replaced by the content of the EPROM of the Versa64Cart. The Reset vector is located at 0xFFFC and 0xFFFD. This is a guidepost for the microprocessor, which shows where to start the execution after the processor was powered up (or received a RESET pulse). This way, the software in the EPROM will completely take control.
The code in an Ultimax cartridge expects to be mapped to these memory regions and won't run from anywhere else. But, it is a simple matter for the PLA to activate the ROMH line and deactivate all the other lines (including the KERNAL) when its address lines read either $E or $F, and the EXROM and GAME lines indicate a MAX cartridge is plugged in. It's just a byte stored at that address of the PLA's memory.
Δυστυχώς είμαι απαισιόδοξος γιατί έριξα μια γρήγορη ματιά στο pdf και αναγράφει ότι "is not suitable to run a kernal..."...κι εγώ Δημήτρη έχω τις επιφυλάξεις μου, αλλά από την άλλη πάλι διαβάζοντας το κείμενο κάτι με τρώει να το δοκιμάσω!![]()
Δυστυχώς είμαι απαισιόδοξος γιατί έριξα μια γρήγορη ματιά στο pdf και αναγράφει ότι "is not suitable to run a kernal..."
Ελπίζω στην επιμονή και των δύο σας και στην πιθανότητα να έχω καταλάβει λάθος...
The Versa64Cart is not suitable to run a Kernal or software, which require bank switching by that software (e.g. games > 16k).
Mode | ROM | GAME | EXROM | Notes |
---|---|---|---|---|
ROML | LO | Open | Close | Most common setting |
ROMH | HI | Close | Close | Used for 16 KB cartridges, so does not apply here |
Ultimax | HI | Close | Open | Originally used for cartridges for the Japanese MAX Machine, will work even if the kernal ROM is damaged |
Gregory Nacu Hi, that's a good question. Unfortunately, it is not possible to replace the KERNAL ROM (or the BASIC ROM) with a Versa64Cart. The Versa64Cart is for expansion ROMs only. The chart in the "extended memory map" section above shows where the the Versa64Cart's ROMs can be mapped. If configured in Ultimax mode, an 8K external rom will be mapped in where the KERNAL is, but unfortunately, it has sweeping changes to the rest of the C64's memory map too. The least expensive way replace the KERNAL via an external cartridge, as far as I know, is the EasyFlash 3. I'm not certain if the regular EasyFlash can also change the KERNAL ROM. |
Πράγματι το Ogryzek είναι μια εξαιρετική επιλογή!Πάντως αν είναι να χρησιμοποιήσεις cartridge για επιτάχυνση διαδικασιών loading, τότε Ogryzek is your friend. Άσε που με το Jiffy αποχαιρετάς την κασέτα. Με το Ogryzek θα έχεις turbo load και σε tape (δεν το έχω δοκιμάσει...ακόμα)
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Ο Skoe το έχει ήδη "ψήσει" με το Easyflash3 που δίνει χώρο στο cartridge για οκτώ kernals!