Search found 1405 matches
- Mon Jan 25, 2021 3:30 pm
- Forum: 8-bit acorn hardware
- Topic: Problem with Master 128
- Replies: 7
- Views: 244
Re: Problem with Master 128
While waiting for a Master expert to chime in... Teletext chips don't fail often but sockets do. Have you tried cleaning/reseating any socketed chips? (My Master has very few most chips are soldered directly... but worth a try).
- Sat Jan 23, 2021 12:46 pm
- Forum: programming
- Topic: C compiler
- Replies: 4
- Views: 186
Re: C compiler
I use itzor's gcc port (latest is gcc8). It kinda needs some backend work to be truely useful as the pointer dereferencing in particular produces some terribly clunky code. He hasn't touched the repo on githhub for a couple of years now though :( I have looked at the backend but they are flipping co...
- Sat Jan 23, 2021 9:13 am
- Forum: 8-bit acorn hardware
- Topic: No -5v after recap
- Replies: 25
- Views: 881
Re: No -5v after recap
I've seen a hairline fracture in one of the -5v tracks on one PSU before now. If you have the same model PSU the -5v track runs very close to one of the screw holes... I had a crack propogate from the screw hole (overtightened by soemone probably) through the PCB and copper. Very hard to spot.
- Thu Jan 21, 2021 1:57 pm
- Forum: general
- Topic: Remarkable videos recently posted on Youtube
- Replies: 370
- Views: 60642
Re: Remarkable videos recently posted on Youtube
There are more good interviews with experts on Robert Feranec's electronics/PCB channel.
Splitting ground planes
Crosstalk
Splitting ground planes
Crosstalk
- Tue Jan 19, 2021 9:04 am
- Forum: 8-bit acorn hardware
- Topic: B+ DFS & ADFS versions for PAGE E00
- Replies: 10
- Views: 818
Re: B+ DFS & ADFS versions for PAGE E00
Doing it this way would avoid the need for the load-to-RAM. And I bet Chris Morley could get it on a very small board with reprogrammability? - Chris . . . ? It would be possible to do a board with an surface mount EEPROM on the top (like my 64KB EEPROM module) and 32KB SRAM + 22V10 PLD on the bott...
- Thu Jan 14, 2021 4:28 pm
- Forum: programming
- Topic: assembler noob
- Replies: 17
- Views: 332
Re: assembler noob
The JMP will assemble with an absolute address. When you run the second program the memory allocated by the DIM is unlikely to be at the exact same absolute address. If you reload the code at the wrong address then all absolute instructions still point to their original absolute position... which is...
- Sun Jan 10, 2021 12:14 pm
- Forum: off-topic
- Topic: Aliexpress VAT
- Replies: 14
- Views: 386
Re: Aliexpress VAT
The limit has been removed by the UK. The €15 limit is due to be removed by the EU.
- Sat Jan 09, 2021 10:32 pm
- Forum: programming
- Topic: Notepad++ with BBC Basic?
- Replies: 9
- Views: 416
Re: Notepad++ with BBC Basic?
It is easy to edit the keyword list. You could add the assembler tokens too pretty quickly.
- Sat Jan 09, 2021 2:15 pm
- Forum: 8-bit acorn hardware
- Topic: VideoNuLA ROM Image
- Replies: 6
- Views: 372
Re: LOLPRICE
https://www.ebay.co.uk/itm/Vintage-Comp ... Swbd5ekgs1
The £599 model B is back now with a "cash only" request in the description.
edit: they have the same thing listed three times...
The £599 model B is back now with a "cash only" request in the description.
edit: they have the same thing listed three times...
- Fri Jan 08, 2021 5:46 pm
- Forum: new ideas wishlist & general chat
- Topic: what should i write next?
- Replies: 364
- Views: 37280
Re: what should i write next?
Ah, so for £40 for a couple of BooBip modules, any model B can have a nice big RAM space for games to work with. Excellent! (That's only 10% extra on the machine price, in round numbers) A bit less £ than that but yes... Another thing worthy of note is you can also replace the CPU vectors (reset, I...
- Fri Jan 08, 2021 4:58 pm
- Forum: new ideas wishlist & general chat
- Topic: what should i write next?
- Replies: 364
- Views: 37280
Re: what should i write next?
Yes with the OS RAM + 1 bank of sideways RAM you can have 79KB of RAM in use without changing any paging registers (or 63KB if you keep the OS paged in for code) - on a otherwise standard model B.
Re: LOLPRICE
£599 for a model B anyone? oh plus £30.30 (not a typo) economy delivery...
https://www.ebay.co.uk/itm/Acorn-BBC-Co ... Swbd5ekgs1
https://www.ebay.co.uk/itm/Acorn-BBC-Co ... Swbd5ekgs1
- Sat Jan 02, 2021 7:19 am
- Forum: 8-bit acorn hardware
- Topic: Unknown upgrade functions, new beeb owner
- Replies: 12
- Views: 573
- Fri Jan 01, 2021 3:20 pm
- Forum: 8-bit acorn hardware
- Topic: Unknown upgrade functions, new beeb owner
- Replies: 12
- Views: 573
Re: Unknown upgrade functions, new beeb owner
from BooBip ... (though he doesn't seem to ship to the Netherlands ATM, probably due to brexit) Aside from the Gotek are there any other recommended storage solutions? I remove all my stuff from eBay around Christmas every year. I get a few item not arrived cases opened against me each year with pe...
- Fri Jan 01, 2021 10:30 am
- Forum: 8-bit acorn hardware
- Topic: Unknown upgrade functions, new beeb owner
- Replies: 12
- Views: 573
Re: Unknown upgrade functions, new beeb owner
I only know of one game that supports the WE shadow RAM, assuming that is what it is and that is my Astro Blaster, but there are probably others. I think its main use was as a printer buffer, but again I could be wrong. I think some adventure games can use it for reduced loading/increased graphics....
- Wed Dec 30, 2020 12:52 pm
- Forum: off-topic
- Topic: Mancave advice needed!
- Replies: 10
- Views: 516
Re: Mancave advice needed!
If it is damp the machines will corrode & might stop working eventually. If it is dry then shouldn't be a problem.
Hot/cold cycling is only really bad if there is humidity/moisture as it promotes condensation and corrosion.
Hot/cold cycling is only really bad if there is humidity/moisture as it promotes condensation and corrosion.
- Tue Dec 29, 2020 10:18 am
- Forum: 8-bit acorn software: other
- Topic: !Boot
- Replies: 9
- Views: 344
Re: !Boot
Would soft keys work for you? Program the soft key in the !BOOT & invoke.
- Sat Dec 26, 2020 11:16 pm
- Forum: programming
- Topic: Notepad++ with BBC Basic?
- Replies: 9
- Views: 416
Re: Notepad++ with BBC Basic?
I use this one I found on the internet years ago. I can't remember the original credit.
- Sat Dec 26, 2020 10:06 am
- Forum: 8-bit acorn hardware
- Topic: Did the Master ever get a second RISC processor?
- Replies: 8
- Views: 544
- Thu Dec 24, 2020 8:55 am
- Forum: 8-bit acorn hardware
- Topic: Program Corruption in memory
- Replies: 16
- Views: 780
Re: Program Corruption in memory
So from that I can confirm that bit 7 is faulty in CAS0....My deduction therefore leads me to believe that IC68 is the culprit....am i right? Your logic seems sound. Inverter connected so 0x4nnn is CAS0. Bit 7 -> 0 at some locations. Bit 7 CAS0 is IC68 as you say. edit: This also lines up with RR's...
- Tue Dec 22, 2020 5:47 am
- Forum: 8-bit acorn hardware
- Topic: Help Please - CPLD Fitter Issues
- Replies: 16
- Views: 517
Re: Help Please - CPLD Fitter Issues
I don't understand why you are using arrays. Why aren't you using normal n bit registers?
reg [7:0] a;
reg b [0:7];
a is an 8-bit vector
b is an array of 1 bit vectors
They are not the same thing and not interchangable AFIK.
indeed...
reg [15:0] c [0:3];
would be a 4x 16bit array.
reg [7:0] a;
reg b [0:7];
a is an 8-bit vector
b is an array of 1 bit vectors
They are not the same thing and not interchangable AFIK.
indeed...
reg [15:0] c [0:3];
would be a 4x 16bit array.
- Mon Dec 21, 2020 8:39 am
- Forum: off-topic
- Topic: Forgetful Television
- Replies: 6
- Views: 405
Re: Forgetful Television
If it has an EEPROM/FLASH for storing the config these do wear out.... could be that. Can be a problem on older car stereos apparently with them turning on at full volume (because they forgot the last setting). You could try opening it and seeing what is inside... or you can live with it... or you c...
- Mon Dec 21, 2020 6:47 am
- Forum: 8-bit acorn hardware
- Topic: BBC Model B and continuous beep unless S25 is set south..
- Replies: 16
- Views: 720
- Sun Dec 20, 2020 6:36 am
- Forum: new projects and releases: demoscene
- Topic: b-tracker
- Replies: 15
- Views: 708
Re: b-tracker
Not sure what you mean by 33-bit frequency; the sound chip uses 10-bit pitch IDs internally, which are looked up from the b-tracker note number by a table. I assumed Richard was talking about the total bits to program the sound chip VGM style... 3x10bit (tones freq) + 2bit (prng freq) + 1bit (perio...
- Sat Dec 19, 2020 11:58 am
- Forum: 8-bit acorn hardware
- Topic: BBC Model B and continuous beep unless S25 is set south..
- Replies: 16
- Views: 720
Re: BBC Model B and continuous beep unless S25 is set south..
Those screenshots do look weird. You might well have 2 faults, a RAM fault + a video fault :/
- Sat Dec 19, 2020 10:36 am
- Forum: programming
- Topic: Reclaiming sound, serial, speech etc workspace
- Replies: 14
- Views: 535
Re: Reclaiming sound, serial, speech etc workspace
FWIW, it seems that *EXEC uses 1100 and 1200, so while loading files there works fine in bench testing, trying to load from a !boot script causes weird errors and corruption (including disk errors!). I think that is why people put CLOSE #0 in their !BOOT file - to close the *EXEC file handle. e.g. ...
- Fri Dec 18, 2020 7:59 am
- Forum: 8-bit acorn hardware
- Topic: Write-up of Western Security floppy disc protection
- Replies: 11
- Views: 739
Re: Write-up of Western Security floppy disc protection
We'd need to believe the duplicator's drive has surprising precision for 1985, but the PDF linked above does bang on and on about quality. Why are you surprised that something precision could be engineered in 1985 in a money no object commercial/industrial device? Take a look at some eevblog vintag...
- Fri Dec 18, 2020 7:27 am
- Forum: 8-bit acorn hardware
- Topic: BBC Model B and continuous beep unless S25 is set south..
- Replies: 16
- Views: 720
Re: BBC Model B and continuous beep unless S25 is set south..
Back.. I finally got the SN74LS04N and made the fancy address inverter to S25. The machine boots up in 32K mode - hooray! However, there's still weird stuff ongoing. The inverter has not fixed anything, it just adds evidence that you have a RAM fault in the bank which is now mapped to 4000-7fff (us...
- Tue Dec 15, 2020 6:11 pm
- Forum: off-topic
- Topic: Soldering help - tip shaft sizes.
- Replies: 20
- Views: 737
Re: Soldering help - tip shaft sizes.
Mate the din connector. The added thermal mass of the mating half reduces plastic melt but also helps keep the pins in the right place if it does melt.