Search found 2688 matches

by BeebMaster
Tue Apr 16, 2019 8:40 pm
Forum: hardware
Topic: Last Gasp for the 8271
Replies: 12
Views: 389

Last Gasp for the 8271

Amazingly, or maybe even adorably, I still get a handful of requests for the trusty old 8271 every year. I think I may now have sourced some after a few years of drawing a blank, I'm just seeing if I can get a reasonable price on them. If I can I might try to do a very very very last ever never to b...
by BeebMaster
Mon Apr 15, 2019 3:20 pm
Forum: hardware
Topic: BeebSCSI 7_7
Replies: 113
Views: 4085

Re: BeebSCSI 7_7

The first issue is probably due to the file server making multiple requests or sub-dividing the SCSI requests in some way. Just to be clear: this is BeebSCSI being accessed by ADFS using OSWORD &72; the file server isn't running. It's just a loop of OSWORD &72 reads from the same start sector each ...
by BeebMaster
Mon Apr 15, 2019 10:52 am
Forum: hardware
Topic: BeebSCSI 7_7
Replies: 113
Views: 4085

Re: BeebSCSI 7_7

I did some testing over the weekend with firmware 2.5, and it's mixed results. One part of the problem has definitely gone, which is that there is no longer any slow-down when sequentially stepping through a disc "image" from start to finish: BeebSCSI2-5Test4.png BeebSCSI2-5Test6.png This enables a ...
by BeebMaster
Fri Apr 12, 2019 1:23 pm
Forum: hardware
Topic: Raspberry Pi to 1MHz bus interface
Replies: 64
Views: 2392

Re: Raspberry Pi to 1MHz bus interface

Have I missed these? I thought I put down for some early on.
by BeebMaster
Wed Apr 10, 2019 7:07 pm
Forum: hardware
Topic: BBC ADVANCED TELETEXT RECEIVER
Replies: 8
Views: 237

Re: BBC ADVANCED TELETEXT RECEIVER

Another difference between the Acorn and Morley Teletext adapters is that the Acorn one has 20 page grabbers but the Morley unit only has 1.
by BeebMaster
Mon Apr 08, 2019 11:03 am
Forum: for sale / freebies
Topic: BeebMaster BBC B Econet Kit
Replies: 37
Views: 2630

Re: BeebMaster BBC B Econet Kit

I'm planning to make up another batch of Econet kits over the Easter weekend. I'll post again when they are ready but if anyone wants to spur me on in the meantime please do so!
by BeebMaster
Mon Apr 08, 2019 10:59 am
Forum: software & utilities for the pc, mac or unix
Topic: FWD: fs/adfs on Linux - keep or kill it?
Replies: 8
Views: 347

Re: FWD: fs/adfs on Linux - keep or kill it?

Please keep! it's very handy to have.
by BeebMaster
Tue Mar 12, 2019 12:36 am
Forum: hardware
Topic: My Master internal pics
Replies: 15
Views: 312

Re: My Master internal pics

I hadn't seen that product code ADT11 shown on the serial number ticket before. According to this: http://chrisacorns.computinghistory.org.uk/docs/Acorn/CSN/Acorn_CSNews21.pdf it looks like Acorn were selling just the Master 128 PCB after they had stopped production, under a separate product code.
by BeebMaster
Tue Mar 12, 2019 12:13 am
Forum: software: other
Topic: Drawing a circle in BBC BASIC
Replies: 36
Views: 1370

Re: Drawing a circle in BBC BASIC

Very similar, just highlight the listing and then copy and paste. I made a little video:

http://www.beebmaster.co.uk/Downloads/Brandy.avi
by BeebMaster
Mon Mar 11, 2019 5:47 pm
Forum: hardware
Topic: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)
Replies: 1124
Views: 106355

Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Could we have a configurable, or higher default, RAM allocation for the Native ARM co-pro? 64MB would be great, and the reason I say that is it would allow an entire real-life Winchester disc to be read into RAM all in one go (there can't be many Winnies bigger than 60MB out there) then a quick fidd...
by BeebMaster
Mon Mar 11, 2019 5:29 pm
Forum: hardware
Topic: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)
Replies: 1124
Views: 106355

Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Maybe the order of the ROMs is important to BeebAid? Could it be that it needs to be lower or higher than the ROM with Tube host code (DNFS/1770 DFS)? Perhaps making a 64K ROM has altered the order of the ROMs.
by BeebMaster
Mon Mar 11, 2019 4:53 pm
Forum: software: other
Topic: Drawing a circle in BBC BASIC
Replies: 36
Views: 1370

Re: Drawing a circle in BBC BASIC

The solution I have for dealing with tokenised BASIC files in a readable format (like the output of LIST) is to use Brandy BASIC. Download the file, start Brandy, load it and list it. Then you can copy and paste the listing as necessary. I have a Thunar custom action so I can just right click the st...
by BeebMaster
Mon Mar 11, 2019 4:39 pm
Forum: hardware
Topic: A potential run of BeebSCSI 7.7 (the newest)
Replies: 86
Views: 2563

Re: A potential run of BeebSCSI 7.7 (the newest)

I don't think it's as simple as patching ADFS to access the internal 1MHz bus instead of the external one - because of the way the official AIV SCSI interface implements SCSI and fetches data from the device attached (ie. LV-ROM player), which is subtly different to the way the ST506/SASI implementa...
by BeebMaster
Sun Mar 10, 2019 11:32 am
Forum: hardware
Topic: A potential run of BeebSCSI 7.7 (the newest)
Replies: 86
Views: 2563

Re: A potential run of BeebSCSI 7.7 (the newest)

I'd like 2 of the VFS adapter only, if it's not too late to express an interest.
by BeebMaster
Mon Mar 04, 2019 2:48 pm
Forum: hardware
Topic: Econet pinout
Replies: 10
Views: 1155

Re: Econet pinout

The E01 Acorn Filestore (in-)famously got the clock signal the wrong way round - http://www.heyrick.co.uk/econet/fs/diff.html The internal network clock is fundamentally broken. Namely, the C+ and C- lines are reversed so it provides the opposite mark/space ratio to a conventional clock box. This s...
by BeebMaster
Mon Mar 04, 2019 2:27 pm
Forum: hardware
Topic: BeebSCSI 7_7
Replies: 113
Views: 4085

Re: BeebSCSI 7_7

This is a great news, as it has been a real inhibiting factor when trying to use BeebSCSI with Level 3 Econet file server. I'm looking forward to being able to try it out when the patch is available. I wonder - should the data file not be opened for read/write access on a *MOUNT or *DIR :0 etc. and ...
by BeebMaster
Sun Feb 24, 2019 5:55 pm
Forum: hardware
Topic: Disk fault - replacement cable?
Replies: 28
Views: 716

Re: Disk fault - replacement cable?

The keys will come back to life if you hammer them (with a finger, not a hammer) repeatedly for about 10 minutes.

You can also programme a function key to insert keypresses for non-working keys, just use VDU to display the character on screen and then copy it into a *KEY definition.
by BeebMaster
Sun Feb 24, 2019 5:48 pm
Forum: hardware
Topic: Master crashed????
Replies: 4
Views: 201

Re: Master crashed????

It could be a bad connection causing spurious data to be read from one of the ROMs - looks like a DFS catalogue header is appearing in the third picture. I'd try cleaning all the contacts on the MOS ROM socket and anything else plugged into a cartridge slot or connector underneath.
by BeebMaster
Fri Feb 22, 2019 8:28 pm
Forum: hardware
Topic: Disk fault - replacement cable?
Replies: 28
Views: 716

Re: Disk fault - replacement cable?

Is the drive head actually moving when trying to access a disc? If all you can do is read a catalogue sometimes, the head might be stuck, or obstructed, so it can only access track 0. There might be just enough movement in it to move off track 0 but not as far as track 1 to actually be able to read ...
by BeebMaster
Thu Feb 21, 2019 10:14 pm
Forum: hardware
Topic: Thinking of trying out Pi coprocessor on my model B
Replies: 17
Views: 630

Re: Thinking of trying out Pi coprocessor on my model B

I should have mentioned that I have a level shifter on its way ;) But thanks. I have to shuffle my ROMs about any way, so I'll burn a DNFS one whilst I'm at it. You might already have DNFS if your DFS reports as 1.20. In the absence of any other way of testing, if you try to select it as a language...
by BeebMaster
Thu Feb 21, 2019 9:02 pm
Forum: off-topic
Topic: Retro upgrades, value for money, eBay & why bother?
Replies: 56
Views: 1938

Re: Retro upgrades, value for money, eBay & why bother?

Very good news! I used to always have listings on E-bay for years. it wasn't so bad when I started in around 2002/2003, it really felt like it was the online equivalent of classified ads except with bidding added, but over time it became more corporate and the site became overpopulated with professi...
by BeebMaster
Tue Feb 19, 2019 11:26 pm
Forum: general
Topic: Ideas please for better beep when Second Processor is present
Replies: 34
Views: 1050

Re: Ideas please for better beep when Second Processor is present

I'd settle just for the VDU 7 bleep being restored when a second processor is active, I never understood why it is missing. For many of us I think the short brrrr tone then silence is as much of a fault indicator as the continuous brrrr, so switching on a Beeb that just has the short low bleep makes...
by BeebMaster
Thu Feb 14, 2019 11:15 pm
Forum: upcoming and recent events & exhibitions
Topic: Wakefield RISC OS show 27/4/19
Replies: 74
Views: 2433

Re: Wakefield RISC OS show 27/4/19

All being well, I'll be there.
by BeebMaster
Mon Feb 11, 2019 5:42 pm
Forum: hardware
Topic: More MDFS Repair
Replies: 13
Views: 274

Re: More MDFS Repair

R49 in the working MDFS is measuring 10K, compared to 2.4 in the broken one...so definitely something suspect in that area.
by BeebMaster
Mon Feb 11, 2019 5:21 pm
Forum: hardware
Topic: More MDFS Repair
Replies: 13
Views: 274

Re: More MDFS Repair

Ahhh....the broken MDFS's Z80 was in a ZIF socket. I've put it back into the motherboard socket and it now gives the same size waveform as the working one.
by BeebMaster
Mon Feb 11, 2019 5:18 pm
Forum: hardware
Topic: More MDFS Repair
Replies: 13
Views: 274

Re: More MDFS Repair

It's difficult to get a picture of the working MDFS before all the lights come on, but this is what happens at A15 on switch on: IMG_3783.JPG Then it's all over the place as the boot sequence starts: IMG_3786.JPG The broken MDFS only gives one image: IMG_3788.JPG I used the same setting so I don't k...
by BeebMaster
Mon Feb 11, 2019 3:15 pm
Forum: hardware
Topic: More MDFS Repair
Replies: 13
Views: 274

Re: More MDFS Repair

The Z80 is OK, it's been tested in another working MDFS. Here's a picture of pin 6:
IMG_3757.JPG
by BeebMaster
Mon Feb 11, 2019 3:04 pm
Forum: hardware
Topic: More MDFS Repair
Replies: 13
Views: 274

Re: More MDFS Repair

R49 goes to +5V and LK3, an unjumpered link. I get 0 resistance from +5V side to another +5V point on the board (pin 1 of the keyboard) and 0 resistance between the link pin and the other side of R49. But still only reading 2.4K.

Also just changed D3, no help.
by BeebMaster
Mon Feb 11, 2019 2:21 pm
Forum: hardware
Topic: More MDFS Repair
Replies: 13
Views: 274

Re: More MDFS Repair

Just replaced it, reads 10.0K after being removed! The new one is reading 2.4K fitted, no change to the operation.
by BeebMaster
Mon Feb 11, 2019 1:45 pm
Forum: hardware
Topic: More MDFS Repair
Replies: 13
Views: 274

Re: More MDFS Repair

OK.

Actually I am now beginning to suspect the area next to the battery (D3, C3, R49, R6). C3 has already been replaced on a previous occasion but I am not getting steady readings from R49 and R6. In particular R49 seems to be settling around 1.9K when it should be 10K.