Master sideway ram question

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archie456
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Master sideway ram question

Post by archie456 » Mon Nov 04, 2019 10:54 pm

Hi,

I know the BBC Master has 4 banks of sideways ram.

I have two pascal roms, if I install them (for some reason they appear as one in the *ROMS list) will they occupy one of the banks of sideways ram - leaving me three left?

I've tried to get the ROMS to appear at position 0, but I cant. I think its one of the rom slots that uses that position.

I'd appriciate some advise.

Thanks.

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jms2
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Re: Master sideway ram question

Post by jms2 » Mon Nov 04, 2019 11:22 pm

I presume you mean two rom images, on disk?

If so, you can only load them into banks 4, 5, 6 or 7 on a master. They would fill two slots, leaving two left. You can't use slot 0 because that is assigned to one of the physical cartridge slots.

Hope that helps!

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flaxcottage
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Re: Master sideway ram question

Post by flaxcottage » Tue Nov 05, 2019 9:29 am

Acornsoft Iso-Pascal should appear twice in the *ROMS output in positions 4 and 5 (if that is where they were loaded) indicating both ROM slots are occupied.

*HELP will show only one Pascal entry.
- John

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johnkenyon
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Re: Master sideway ram question

Post by johnkenyon » Tue Nov 05, 2019 11:55 am

archie456 wrote:
Mon Nov 04, 2019 10:54 pm
Hi,

I know the BBC Master has 4 banks of sideways ram.

I have two pascal roms, if I install them (for some reason they appear as one in the *ROMS list) will they occupy one of the banks of sideways ram - leaving me three left?

I've tried to get the ROMS to appear at position 0, but I cant. I think its one of the rom slots that uses that position.

I'd appriciate some advise.

Thanks.
IC27 provides one 16K slot, without sacrificing any sideways RAM.
IC37 will allow you to install a 16K ROM or a 32K ROM containing 2x 16K images, however enabling this socket, will disable 2 banks of sideways RAM.
Same goes for IC41.

This means you have one of the following options

1) Install the ROMS in a cartridge, and lose no sideways RAM.
2) Install one ROM in IC27, and the other in IC37 or IC41, setting the required links - you will lose 2x 16k sideways ram banks
If IC27 is already occupied, and you don't have a cartridge
3) Burn the two 16K ROM images into a single 32K EPROM, install in IC37 or IC41, set the required links and lose 2x 16K sideways RAM banks
4) Install the two 16K ROMS in IC37 and IC41, setting the required links - you will lose 4x (=all) 16k sideways ram banks.

If I were in your position, I would go for option 1 or option 3 (I consider IC27 to be the ANFS/<insert name of other MMC/CF type filesystem> socket)

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archie456
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Re: Master sideway ram question

Post by archie456 » Tue Nov 05, 2019 9:25 pm

Thanks for your replies guys - annoyingly the only TV i have that I can connect the Master to has fused and so I can't check whats going on.

I'll let you know what roms I can see when another 5A fuse!

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marcusjambler
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Re: Master sideway ram question

Post by marcusjambler » Tue Nov 05, 2019 10:49 pm

I've got one of the IFEL master cartridges that allows 4 banks of 2 switchable battery backed images.
Plus a 28 pin socket... They pop up on ebay fairly regularly

Marcus

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archie456
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Re: Master sideway ram question

Post by archie456 » Sat Nov 09, 2019 2:14 pm

OK, got the monitor running again.

I reinstalled the two Pascal roms and Smart SPI and so all the Masters on board slots are full, see picture.

https://pasteboard.co/IFTDUAH.jpg

After typing *ROMS, I found that slots 7 to F are all full - so I guess that means that I now have only two banks of SW ram available as johnkenyon said.

https://pasteboard.co/IFTGoXG.jpg

I think I'll get a rom catridge as this seems the simplest solution, I would like to keep 4 banks of SW ram available.

Strangely, whilst I've installed the two Pascal roms, it only appears once in *ROMS - perhaps one of the roms is faulty? Nonetheless, Pascal runs OK if I type *PASCAL and the Master goes to the '%' prompt.

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archie456
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Re: Master sideway ram question

Post by archie456 » Sat Nov 09, 2019 2:36 pm

Damn... Just worked out the issue.

I installed Smart SPI into IC37 - but found that in *ROMS it wasn't listed at all.

I then removed Smart SPI and put the two Pascal roms in IC37 and IC47 - and bingo, the two roms of Pascal were listed in slots 6 and 7.

I guess that means that the IC37 slot on the motherboard is somehow faulty... Are they easy to fix? I'll probably not bother fixing it (beyond my skills) and just live with using SW Ram images.

But I suppose the issue is that I now can't install the Smart SPI rom without losing some SW ram banks.

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