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About morelenmir

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    West Yorkshire, Great Britain
  • Currently Playing
    'Remember Me' - a really nice and overlooked distopian blend of 'Deus Ex' and 'Assassin's Creed'. Its a shame Capcom crashed before they made any more in the series.
  • Playing Next
    Prince of Persia - The Forgotten Sands. The PoP games for the original XBox are my favourite third-person action games of all time. This 360 release escaped me at the time so I am quite looking forward to giving it a bash thanks to XBox Live!
  1. Is there any chance that some kind of system to allow *.CAS images to be played back from different points in their run length? For instance, as it stands now all cassettes are played from the beginning. However I have quite a few compilation cassettes that have multiple programmes on them then begin consecutively along the tape. It would be very convenient to be able to 'fast forward' or 'rewind' to one of the later/earlier programmes. I mentioned this once to JoeyZ but--totally understandably--his focus was elsewhere at the time. It wouldn't need to be anything super fancy like a waveform and visual selector. Just an edit box where you could manually enter the time offset to begin from would be absolutely fine, although a horizontal slider that scrubs from the start time to the finish time would be even better while remaining minimalist. The latter would also automatically take care of bounds checking. Obviously these are all nothing more than polite suggestions and nebulous ideas. Absolutely no demands of any kind are being made!!!
  2. In my case--yep, I independently identified and attempted all the fixes you suggested. I also downloaded the tool to modify the firmware on the FTDI device itself and then changed the 'sleep' setting to never occur. Absolutely no difference. I am pretty sure it was some kind of edge case with my very old motherboard. The reset button solved my problems pretty much, but I don't think that could be applied in all cases unless everyone wants to start getting in to traditional electronics projects type modding. I also agree with your suggestion of sticking to COM based SIO2PC. I have even recently bought a COM add-on card, since despite the age of my computer it was still just at the end of the era where they were a standard part of the motherboard--although annoyingly it does have an LPT port! Once I get around to installing that I am going to try assembling an SIO2PC based on one of the old designs for the COM interface. Hopefully with a direct connection like that then true XF551 emulation can finally be implemented. I would just buy one of the AtariMax devices, but when combined with the cost of APE and international post the price becomes a ridiculous £100+!!! Plus it doesn't even come in a case! A far cheaper solution is the SDrive MAX. l now have a working unit, which once I finally get a 3D printed case will make most of the SIO2PC superfluous I think. Hopefully, since it too uses a direct connection to the SIO signals and does not go through the slower intermediary of a USB interface the device can be convinced to do true XF551, Happy and so on emulation. It already does ATX.
  3. My non-Chinese Sparkfun FTDI break-out implementation does exactly the same thing--stop working when left for a while. This is why I added a momentary push-switch between ground and the reset leg (leg 19 I think?) to quickly reinitialize the USB connection without having to reach behind my machine and fumble around unplugging and then replugging. It is also why I don't use the official FTDI USB cables with the chip built in to the cable as none of the signals they offer are the reset pin (along with the insane £17 price tag!). Plus I like blinky LED's to tell me something is happening on send or receive! My system is an eleven year old Win7 machine and it has shown this behaviour since all the way back at R2.
  4. Is the source code open to learn from and adapt if we can think up improvements?
  5. I like the type-in BASIC game 'BowlTrap'. It was published in 'Page6' magazine, issue 31. It begins on page 68 and is pretty short but the colours and gameplay show the A8 to its very best. There is also an excellent font editor programme in the same issue called 'Font Factory' which begins on page 20. Finally, yet again from the same number and beginning on page 58 is 'Original Synth'--a pretty good attempt at a POKEY-based synthesizer with rudimentary visualisation. Les Ellingham must have been at the top of his game that month because these three programmes are absolutely first rate and have stayed with me for nearly thirty years. All 'Page 6' listings are printed with a two-letter checksum at the left of each line. These work alongside the 'TypoIII' memory resident programme. In order to use this you must load and run 'TypoIII', then without pressing System Reset begin entering the programme as usual. Every time you press Return a matching (if you have entered it correctly!) two character checksum is calculated and displayed at the top of the screen which you can compare against the one in the magazine.
  6. Yep, it sounds like you've got the process down without any problems. As things stand I think the key is to always use Radioman's flasher to upgrade (or downgrade if you ever want to check out an old version or whatever) instead of allowing the client software to do it automatically. I suppose its adds some extra degree of complexity and you'll have to keep the custom flasher on your hard-drive somewhere, but its really very simple and the programme itself is tiny, so... I honestly can't think of any other reason not to! In regards which version to update with; I have been using v6.82 now for about two months without any problems at all. I totally understand you not wanting to run the risk, but I don't think you'll encounter any issues if you do decide to take the plunge. I also think its worth repeating the suggestion to take a note of your original Serial number and Device ID--ideally before you even do the first cross-flash. That way you are covered from every angle. The only other thing you might want to do is slightly mod the TL866 itself. I have mounted a small two position slide-switch (eBay Auction -- Item Number: 290553778931) to the outside of the case, wiring just two of the contacts to place a 200ohm pull-up between RC1 and a source of 3.3V. If something like this ever happens again I can flick the switch and set the device into its boot-loader mode without having to unbutton the case and solder/desolder a resister. At all other times the switch is off, RC1 is low and the flasher works like normal. You just need to Dremell a small slot for the switch and two screw holes for its mounts.
  7. This evening I have bought an 'ELEGOO 2.8Inch touchscreen TFT display' (eBay Auction -- Item Number: 163302297706) for just over £16 and an Arduino UNO R3 clone (eBay Auction -- Item Number: 262200725666) for a little under £5. Going from the Google translation of the 'SDrive MAX' page I think these components will do the job. Luckily--just as the web page mentions--this type of Uno clone does have extra pads beside the TX/RX sockets which make it very convenient for connecting the appropriate SIO signals. However one practical aspect which I do not like about the design is the fact the SIO cable is connected directly to the Arduino motherboard and then runs out to the Atari with at best a cable grip as strain-relief. I would prefer there to be an intermediary stage added to this; wires to connect the appropriate Arduino pins to a DIN (or some other) socket that is attached to the case and then a matching plug which connects the actual SIO cable that goes on to the Atari. This way any snag or accidental pull on the cable does not yank off the TX/RX pads from the Arduino! I have asked my best pal who is 3d printing the case for me if he can add a bit of length to the design so I can fit a DIN socket inside it. All in all though I am very much looking forward to having a bash at this project when the boards arrive in the post! One question that strikes me is; since the SIO signals are directly connected to the Arduino without the intermediary of a Serial-to-USB converter as in the SIO2PC-USB device does this mean that full emulation of the XF551--which is highly dependent on proper timing--can be done inside the 'SDrive MAX' software?
  8. I have had a great deal of luck in replacing all the 'LS' type 74-series logic with 'AHCT' versions. I think the CMOS circuitry inside them is much better at handling potentially noisy inputs. The ACHT ICs are also specifically made to be compatible with 5V TTL logic and act as direct 'drop in' replacements for matching 74-series number designations. For a long time I substituted the Fairchild 'F' type logic but eventually learned these ICs, while faster to respond to signals are actually more sensitive to noise. At least this is my own experience--my 130XE barely works using LS logic while modded with U1MB, VBXE and SimpleStereo. However if I swap out the originals for AHCT ICs it runs almost perfectly. The 'almost' is due to other factors not linked to the logic units.
  9. I am absolutely fascinated with all these different projects that have been done to improve and customize the OS. It is nice to come across something implemented in the existing hardware! I would certainly like to extract the Altirra OS FP and even math routines and put them into the stock OS. However that is my sticking point at the moment. I know--more or less!--what these patches are for, but I currently don't understand how to apply them physically to a file image of the stock OS. Did anyone ever produce that ABBUC project to write a custom rom 'factory' patcher that David_P mentioned?
  10. and Many thanks indeed guys!!! It looks like I need to update my U1MB! In regards getting at the Altirra BASIC ROM, that is pretty much what I was wondering. I have been away from the A8 so long, especially as emulated that I am a bit out of touch. Exporting the ROM image seems like a way to reliably get hold of the newest whenever a new iteration Altirra appears. I guess Phaeron no longer offers it as a separate file from the get go?
  11. is Altirra BASIC v1.44 still the newest? For some reason I can never find the latest release whenever I check for a new one, although I am absolutely sure it is staring me in the face!!!
  12. Are you sure this doesn't contain an inadvertent ROM dump for Polybius??? I always get an eerie feeling when things like this appear straight from the murky days of the early eighties...
  13. Many thanks indeed guys!!! I can see I have tapped in to a rich seam of ideas here! At first I liked the idea of a built-in or at least cartridge'd version of TBXL, however I think Phaeron's 'Altirra BASIC' offers many of the same advantages--even direct control of P/M G--and that slots perfectly into the 8K allotted for BASIC without any shoehorning at all. I do know he deliberately left the FP routines as they were in a sort of pass-through arrangement to Altirra since the emulator itself offers the option of patching the OS code on the fly. However when you use Altirra BASIC on a real computer then you are falling through to the stock OS. Hence my interest here. it was pretty much a process like that which I envisioned. Is there an utility to do the patching or is it just a case of manually finding the right place in the OS image file and then copy and pasting the new routines over it with a hex editor? Larry also mentions the possibility of re-checksum'ing the finished item. In regards the idea Gunstar mentions of banking in and out to extend the OS, I have wondered about exactly that process in regards extending the potential space for the PBI BIOS. Obviously this is all hand-wavy/blue-sky talk, but in general would it be possible to do something like that? Obviously I am not requesting a circuit plan and a BOM for the finished project!!!
  14. While looking at the various alternatives versions of BASIC that are available I became quite interested in the floating point routines that are housed in the OS ROM. From what I have read these are notoriously badly written and very slow. Apparently just using better routines will speed up execution of even the native version of BASIC. I found out through a little further research that a fellow called 'Charles Marslett' wrote greatly improved floating point code way back in the early days of the 400 and 800. He very kindly offers the source code for these routines on his website: http://www.wordmark.org/mydos.html I was wondering if it is possible to build these routines and directly patch the stock OS ROM code with them?
  15. I think MrFish was involved in preparing some of the ROM's--therefore I have no doubt they work as advertised. But, as FJC says the 32K ROM that is rather mystifyingly ladled 'built-in' won't fit in 8K of BASIC EEPROM nor an alternative like the U1MB. So... I think UltimateCart would probably work if you ran the provided *.CAR image through the HTML cartridge conversion programme that ElectroTrains wrote. In regards TBXL itself; I really would like to use it as my default BASIC given how highly it is regarded, not to mention its greatly improved speed over Atari BASIC. However, on the latter score Altirra BASIC is pretty dam fast and that really is a direct 'drop in' replacement--only it still uses the stock OS FP code. Therefore I am now looking at getting the best of both worlds with Altirra BASIC in tandem with one of the custom OS ROMs that improve on the slow FP routines--MyBIOS seems the obvious choice. That has nothing to do with TBXL though!
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