Shadow add-ons for the B are a bit kludgy by nature. The video circuitry will only access the original onboard memory so you have to keep paging in/out the shadow ram; doing it properly requires intercepting OSWRCH, OSRDCH, OSBYTE and OSWORD calls (and that's just to do B+ style). I did this BITD with the Solidisk 2M128 board but ended up rarely using it. So much so that when I got my second B I just went with an IFEL board; it gave 4 ROM, 4 Flash, 8 RAM slots so I could load up my favourite ROMs and still have 8 ram banks free.I’m (partially) surprised nobody’s mentioned Shadow RAM yet. The more ultimate you go, the more RAM gets stolen and the less you have to play with. Shadow gives you some back, although it is harder to get hold of.
So I wouldn't bother with Shadow on a B unless you plan on writing large programs yourself; nothing else will use it. But see later for CoPro...
(Talking of the Solidisk 2M128; it works just fine with econet; I wonder if it's the 4M256 variant that breaks things, or just the very bad original Solidisk manager ROM - I wrote my own Image may be NSFW.
Clik here to view.
).Other expansions for the "ultimate" machine would include UPURSFS (https://sweh.spuddy.org/Beeb/UPURSFS/) or, at the very least, the original UPURS ( http://www.retro-kit.co.uk/UPURS/ ). I end up using UPURSFS more than I use my Gotek or TurboMMC.
Ah yes, TurboMMC - I actually find that more useful than Gotek if I want to play games. I have that ROM loaded permanently in my Beeb and just load Solidisk DDFS (from UPURSFS) whenever I want to access Gotek. In theory the Gotek is truer to the BITD experience, but I find the MMC experience just a little bit better. Having two DFS-like ROMs in the Beeb at the same time isn't optimal, which is why I don't have both ROMs in at the same time.
Note that TurboMMC and UPURSFS both need the User port so can't be used at the same time; I built a 2nd user port via the 1Mhz bus to solve this ( https://sweh.spuddy.org/Beeb/2nd_User_Port/ )
Of course, for the true experience you need some sort of tape drive; no BBC is complete without a "load from tape" experience Image may be NSFW.
Clik here to view.
I connected it to the sound card in my PC just to prove I could do it; I mostly stopped using tape BITD once I got floppy drives Image may be NSFW.Clik here to view.
But there are modern tape drive alternatives (eg tzxduino) that should work with the Beeb (I've not tested) that will give the experience of tape drives with the flexibility of SD cards.To complete connectivity, something plugged into the serial port; in my case I have a serial cable plugged into my Linux machine so I can load the Kermit ROM (from UPURSFS; I said I use it a lot!) and get a terminal login session running. Maybe more fun are the new "Wifi modem" boards which let you make connections to machines over the internet as if you were doing a dialup modem experience.
And finally you want a 2nd processor. I have the matchbox copro, but there's also the ability to use a rPi. Both of these allow for different copro CPU models to be used so you can play with different OSes. Even if you stick with the 6502 model this gives you faster processing and more RAM (even more than you'd get with Shadow) and is well supported since the Beeb was designed to do this.
So that's my current B; Sideways RAM (STL 2M128 / IFEL), Gotek via STL FDC (with DDFS loaded on demand), UPURSFS (via 2nd user port), TurboMMC, Matchbox copro, econet, tape, serial. I also have the original analogue joysticks. And video out via an RGB to VGA adapter so I can use an LCD monitor.
Statistics: Posted by sweh — Wed Apr 09, 2025 2:04 pm