I did this for a friend of mines A4. Recapped the board after one exploded. And replaced the cmos battery.
I can post more details if you’d like them?
Scott.
Search found 152 matches
- Thu Sep 19, 2019 1:47 pm
- Forum: 32-bit acorn hardware
- Topic: A4 Laptop - replacement electrolytic capacitors and CMOS battery
- Replies: 62
- Views: 4491
- Fri Aug 23, 2019 12:23 pm
- Forum: programming
- Topic: Detecting available file systems
- Replies: 17
- Views: 2077
Re: Detecting available file systems
Another question. If I write a routine in assembly to cycle through the file systems how do I capture/handle the errors? (For example is basic we use ON ERROR GOTO XXX.) Is it a matter of redirecting the BRK vector to my own error handling routine or is there another method? What is best practice? I...
- Wed Aug 21, 2019 9:10 am
- Forum: programming
- Topic: Detecting available file systems
- Replies: 17
- Views: 2077
Re: Detecting available file systems
Thank you all for your input. Its very much appreciated.
Just one last question. I was also wanting to know if you can detect if a drive is connected to an interface. Is this possible without the system just hanging?
Just one last question. I was also wanting to know if you can detect if a drive is connected to an interface. Is this possible without the system just hanging?
- Mon Aug 19, 2019 10:03 am
- Forum: programming
- Topic: Detecting available file systems
- Replies: 17
- Views: 2077
Detecting available file systems
Hi All, What is the best method for detecting the available file systems in a Beeb? (ie: How would you program it in a program?) Is it just a matter of probing all the sideways ROMS and discovering DFS, NFS, ADFS, etc... or is there another method? Also is there a way of detecting if a floppy drive ...
- Fri Nov 09, 2018 1:16 pm
- Forum: 32-bit acorn hardware
- Topic: A3020 IDE Hard disks setup (revisited)
- Replies: 5
- Views: 920
Re: A3020 IDE Hard disks setup (revisited)
If I recall correctly its a basic program so you can modify it. I recall modifying the sectors, heads, etc. for one of the defined hard drives in the program to settings I wanted and it worked. FYI: You can also load the Wizzo rom on the A3020 which will let you have 4 partitions of 512Mb running on...
- Tue Nov 06, 2018 1:20 pm
- Forum: 32-bit acorn hardware
- Topic: Formatting real harddiscs >512MB on RO3.1
- Replies: 20
- Views: 2905
Re: Formatting real harddiscs >512MB on RO3.1
Ok, thanks for replying so quickly. Yes this is very frustrating, we've been having this problem since we got the mini podule some 2 years ago now. So even after cleaning everything a mechanical hard drive now works reliably but if you tried a solid state drive it would still corrupt. Is that right?...
- Tue Nov 06, 2018 12:25 pm
- Forum: 32-bit acorn hardware
- Topic: Formatting real harddiscs >512MB on RO3.1
- Replies: 20
- Views: 2905
Re: Formatting real harddiscs >512MB on RO3.1
I tried out a different cable, and all seemed well... But only for a day, and now I am seeing Broken Directory errors. There is certainly a fault with the IDE interface, but it is an intermittent one. I'm going to look for dirty contacts and dry joints. Hi, have you had any progress with this. I ha...
- Sun Nov 04, 2018 1:41 pm
- Forum: 8-bit acorn hardware
- Topic: Master ET (Econet Terminal)
- Replies: 15
- Views: 1423
Re: Master ET (Econet Terminal)
Ok, so it looks like its either a faulty resistor R53 10K, a faulty diode D13 1N4148 or a faulty capacitor C22 100nf. These are used to hold the reset line HIGH and will only go low when the break key is pressed on the keyboard performing a reset of the 6502 CPU. So which component would you swap ou...
- Sun Nov 04, 2018 12:44 pm
- Forum: 8-bit acorn hardware
- Topic: Master ET (Econet Terminal)
- Replies: 15
- Views: 1423
Re: Master ET (Econet Terminal)
Ok I've made some progress. I noticed the Reset line being held LOW on the 6502. I traced this back on the schematic to IC39 then back to IC19. If I hold PIN 12 low on IC39 the machine boots to the ACORN MOS this is not a language. So I need to find out whats holding the reset line LOW. Schematic sa...
- Sun Nov 04, 2018 7:09 am
- Forum: 8-bit acorn hardware
- Topic: Master ET (Econet Terminal)
- Replies: 15
- Views: 1423
Re: Master ET (Econet Terminal)
Ok, i've successfully extracted the 6522 from IC8 on the Master ET. I put the extracted 6522 into my model B and its working fine. I've tried the working 6522 from the Model B and tried it in the Master ET. Still have beep of death. What are the next steps with troubleshooting this one? Each time I ...
- Sun Nov 04, 2018 5:56 am
- Forum: 8-bit acorn hardware
- Topic: Master ET (Econet Terminal)
- Replies: 15
- Views: 1423
Re: Master ET (Econet Terminal)
Thanks everyone for your help.
My master ET is about to go under the knife now and extract the 6522.
I tried LK9 and the ROM from my master 128 with no luck.
Its weird how its just died. I haven't used this machine much at all.
My master ET is about to go under the knife now and extract the 6522.
I tried LK9 and the ROM from my master 128 with no luck.
Its weird how its just died. I haven't used this machine much at all.
- Fri Nov 02, 2018 10:18 am
- Forum: 8-bit acorn hardware
- Topic: Master ET (Econet Terminal)
- Replies: 15
- Views: 1423
Re: Master ET (Econet Terminal)
The machine is nearly identical. The Master ET ROM is 4x16K instead of 8x16K, so to use the Master 128 MOS you need to change LINK 9 from 64K to 128K. Thanks Jonathan. First port of call when this happens is always the System VIA (6522)... d. Thanks Daniel, does that mean de-soldering the chip and ...
- Fri Nov 02, 2018 1:52 am
- Forum: 8-bit acorn hardware
- Topic: Master ET (Econet Terminal)
- Replies: 15
- Views: 1423
Master ET (Econet Terminal)
Hi All, I have a Master ET workstation that was working but now is giving me the continuous beep of death. I know a dodgy ROM can cause this and given the current ROM in the machine is an EPROM I'm wondering if its failed. I have a Master 128 and was wondering are the OS ROMS compatible between the ...
- Sun Jun 03, 2018 10:41 pm
- Forum: past events & exhibitions
- Topic: RPCemu at London user group / Mon 18th June 2018
- Replies: 5
- Views: 1236
Re: RPCemu at London user group / Mon 18th June 2018
Lol. Fair enough. Well look forward to hearing what is discussed. Could someone take minutes maybe?
I only suggested it because I recently watched some videos of the Wakefield meetup and was interesting listening to robert sprowson talking about risc os 5.
https://youtu.be/n_Bhm5PmDfg

I only suggested it because I recently watched some videos of the Wakefield meetup and was interesting listening to robert sprowson talking about risc os 5.
https://youtu.be/n_Bhm5PmDfg
- Sun Jun 03, 2018 9:13 am
- Forum: past events & exhibitions
- Topic: RPCemu at London user group / Mon 18th June 2018
- Replies: 5
- Views: 1236
Re: RPCemu at London user group / Mon 18th June 2018
Hopefully someone will video the presentation and post it on you tube for all to see. I'd come but bit of a trek from Melbourne, Australia.
- Sun Jun 03, 2018 9:09 am
- Forum: 32-bit acorn software: other
- Topic: Novell NetWare client for Risc OS
- Replies: 1
- Views: 632
Novell NetWare client for Risc OS
Hi All, Probably not going to be high in demand, but for any Risc OS and Novell NetWare fans out there, there is actually a NetWare client for Risc OS. It can be downloaded for FREE from this website http://www.kingswood-consulting.co.uk/nwclient/ Its IPX only, doesn't support TCP/IP. So should work...
- Sat Jun 02, 2018 7:06 am
- Forum: 32-bit acorn hardware
- Topic: RPC with faulty keyboard interface
- Replies: 23
- Views: 2391
Re: RPC with faulty keyboard interface
Attached is the STATUS settings from my RISC PC after powering on with DELETE held down.
- Fri Jun 01, 2018 6:47 am
- Forum: 32-bit acorn hardware
- Topic: RPC with faulty keyboard interface
- Replies: 23
- Views: 2391
Re: RPC with faulty keyboard interface
Excellent news. Well done! Those pesky CMOS chips do cause a world of pain if there not working don’t they. The reason why the apps aren’t working is with the later versions of RISC OS the apps were relocated from ROM to hard disk to be soft loaded I believe. You might also want to check all the Rom...
- Thu May 31, 2018 11:33 am
- Forum: 32-bit acorn emulators
- Topic: Econet for Arculator (and other emulators)
- Replies: 13
- Views: 3016
Re: Econet for Arculator (and other emulators)
More the merrier. 
I find beebems implementation of econet very buggy. Times out and hangs.
RPCemu is pretty rock solid for RISC OS.

I find beebems implementation of econet very buggy. Times out and hangs.
RPCemu is pretty rock solid for RISC OS.
- Wed May 30, 2018 5:30 pm
- Forum: 32-bit acorn hardware
- Topic: RPC with faulty keyboard interface
- Replies: 23
- Views: 2391
Re: RPC with faulty keyboard interface
I’m not sure re: running self tests on boot up. I’m guessing it must as it would be apart of the ROMs boot up code. The red screen remains on for quite some time, enough time for the monitor to sync, so I'm guessing your machine isn't displaying it. I'm not aware of any jumpers to reset cmos. My mac...
- Tue May 29, 2018 4:44 pm
- Forum: 32-bit acorn hardware
- Topic: RPC with faulty keyboard interface
- Replies: 23
- Views: 2391
Re: RPC with faulty keyboard interface
You might not need to replace it. I’ve just repaired 2 RISC pc motherboards that had suffered battery damage. They both would start with a red screen and then boot. I looked at the circuit diagrams and found a number of tracks had been damaged. Repaired them all and now the cmos is working and no mo...
- Mon May 28, 2018 4:53 pm
- Forum: 32-bit acorn hardware
- Topic: RPC with faulty keyboard interface
- Replies: 23
- Views: 2391
Re: RPC with faulty keyboard interface
Hi, I have this problem with my RISC pc if the cmos isn’t working. Only way the keyboard continues to work is if I hold down delete to reset cmos settings on power on. Red screen comes on for a couple of seconds then goes away and the machine boots. If I don’t hold down delete. The machine would boo...
- Sat May 26, 2018 3:10 pm
- Forum: 32-bit acorn hardware
- Topic: Risc PC CPU Oscillator/Crystal
- Replies: 2
- Views: 616
Re: Risc PC CPU Crystal
Thanks Rob. I’ll take a look.
- Sat May 26, 2018 3:06 pm
- Forum: 8-bit acorn hardware
- Topic: ECONET WOES
- Replies: 74
- Views: 8025
Re: ECONET WOES
I’d recommend version 1.24. Supports you walking up directories (*DIR ^), a huge advantage over earlier versions and has better support for Risc OS and crashes less.
Down side is it’s not Y2K. Can’t specify the correct date and time.
Down side is it’s not Y2K. Can’t specify the correct date and time.
- Sat May 26, 2018 2:55 pm
- Forum: 8-bit acorn hardware
- Topic: Gotek Flashfloppy not recognising blank ADFS discs?
- Replies: 14
- Views: 1468
Re: Gotek Flashfloppy not recognising blank ADFS discs?
Are they fully padded out blank disk images? Would cause problems if there not.
- Thu May 24, 2018 8:56 pm
- Forum: 32-bit acorn hardware
- Topic: Risc PC CPU Oscillator/Crystal
- Replies: 2
- Views: 616
Risc PC CPU Oscillator/Crystal
Hi All, I have a spare dead Risc PC 710 CPU I got when I purchased my RISC pc. I thought I’d plug it in and probe the crystal to see if it was outputting a clock signal. It’s not. So I’m trying to source 80MHZ 4 pin DIP crystal. RS online and element 14 don’t seem to have this type. Anyone able to p...
- Tue May 22, 2018 1:04 am
- Forum: 8-bit acorn hardware
- Topic: ECONET WOES
- Replies: 74
- Views: 8025
- Sun May 20, 2018 7:18 am
- Forum: introduce yourself
- Topic: Hello from Australia
- Replies: 11
- Views: 1241
Re: Hello from Australia
Hi James,
From Blackburn, Melbourne here. Welcome to Stardot.
Scott.
From Blackburn, Melbourne here. Welcome to Stardot.
Scott.
- Wed Apr 04, 2018 3:15 pm
- Forum: 32-bit acorn hardware
- Topic: Acorn A4 hardware repair
- Replies: 2
- Views: 783
Re: Acorn A4 hardware repair
Hi again, Well its been an interesting 24hrs. I've managed to resurrect this A4. Looks like the main problem was corrupt CMOS settings. Holding down delete or R on an externally attached keyboard appears to have no effect on this A4 laptop. Managed to get the grainy display back up and typed in conf...
- Tue Apr 03, 2018 4:29 pm
- Forum: 32-bit acorn hardware
- Topic: Acorn A4 hardware repair
- Replies: 2
- Views: 783
Acorn A4 hardware repair
Hi all, I have a friends A4 laptop which unfortunately blew a decoupling capacitor (went up in flames and smoke). The laptop worked prior to this capacitor blowing. I've since removed all the can surface mount capacitors and replaced them all. Unfortunately a couple of the pads had been badly damage...