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Is this the Atom I recently worked on..... in that case AtoMMC firmware will be in the ROM on the RAMROM.

Cheers.

Phill.

Put me down please,

Arriving Friday, Leaving Sunday, with normal kit

Cheers.

Phill.

Slow CD4000B series CMOS [-X Better off using 74HCxxxx series chips. Try using a 74HC4024 like this CD74HC4024E ;-) I always wondered about that are the 74HC4xxx direct drop in replacements for the 4000 series as long as VCC =< 5V ? It always seemed that way from the couple of datasheets I compared...

Annnnd home again.

Good weekend as always, and good to see you all again, look forward to the next one.

Cheers.

Phill.

Just about to leave Coventry see you all in an hour or so......

Phill

Right anything anyone wants me to bring at the weekend?

Cheers.

Phill.

Indeed I think it's the ICE-T being more forgiving, in this case some of the lines on the CPU data bus only seem to be getting to about 2.5V Time to investigate the 8304s I think, as the Atom also uses them I could try them in there, just to verify, though I'm tempted to think that it could be two t...

Hi all, Still working on trying to make my newly aquired Nascom 3 more reliable, I've changed the CPU socket for a turned pin one so I could try Hoglet's ICE-T Z80 in it. (including repairing a track I managed to lift getting the old socket out, most disappointed in myself for that). Anyway with the...

Hi all, In trying to get FlashFloppy working with my Nascom, Mark H pointed out that it uses identical disk geometry to the L format ADFS disks namely : 80 tracks of 16, 256 byte sectors, double sided. So I got a nascom image and renamed it .ADL, and put it in one of my Goteks, great doing a ]D brin...

Hi all, I may have mentioned that I didn't use Beebs at school, our school being in Coventry used Nascom 3 machines, as I think they where made locally, certainly when Lucas took over. Well I've been looking for one for a few years now and recently managed to bag one from ebay, oddly enough seller w...

tricky wrote: ↑

Mon Oct 29, 2018 10:13 am

Finally got around to booking the hotel, see you Friday evening.

Excellent, bring your Atom, and we can see if we can get it going (if you haven't by then).

Cheers.

Phill.

I'm sure I asked this before...... I serached and could not find it tho..... https://stardot.org.uk/forums/viewtopic.php?f=44&t=7316 I thought I'd asked it before I did try searching, obviously didn't use the correct terms / go far enough back....Ironically I'm testing the same part of the colour b...

roland wrote: ↑

Sat Oct 27, 2018 5:57 pm

Prime wrote: ↑

Sat Oct 27, 2018 10:24 am

Humm that does seem to be it, how primitive that it doesn't ignore whitespace.

What would you expect in a 4 KB rom

There is indeed that

Cheers.

Phill.

IanS wrote: ↑

Fri Oct 26, 2018 9:23 pm

Remove the space after the ; ?

Code: Select all

20 [ JMP #9000;]

Humm that does seem to be it, how primitive that it doesn't ignore whitespace.

Cheers.

Phill.

Hi all, I'm sure I asked this before...... I serached and could not find it tho..... Why does this program : 10 P=#9000 20 [ JMP #9000; ] 30 LINK #9000 40 END Give an error 208** in line 30? If I type the same commands in direct mode they execute as expected..... ** Unknown assembler mnemonic acordi...

Thanks to Phill for showing me Clonezilla, it would have been a nightmare without that, and to everyone who helped. Glad to be of help, and glad it went ok. Clonezilla may have it's rough edges, as it won't shrink partitions, only expand them but it's certainly made my life easier both at work and ...

Humm, This puts me in a difficult position, I had formally passed over production of the DragonMMC boards to Bas / TheCorifot, a few months back but am still getting the odd request for them. For various reasons Bas has not been able to do another run, so I'm not sure what I should do at this point....

How can I tell :oops: It will have "issue x" on the board, where x=1,2,3,4,5. Normally under the video RAM on the same side as the chips. Also externally you can generally tell an issue 5 motherboard as it has beeb keyswitches**, and beeb like keycaps. **Unless like one of my machines it's an issue...

An update on our attempts to archive the MIA tapes and discs in the museum's vaults: I emailed Jason Fitzpatrick, the curator, and he was very positive about Stardotters going down to the museum in person in order to archive his software. So I replied to his email and cc'd Phil, who volunteered upt...

Can't see anything wrong but you never know. Just measured the resistance across one of my Atoms and it's about 350R in one direction and about 375R in the other, so 300ish seems the right ballpark. When you say your PSU displays 0V, I take it it's a bench PSU? What does it display with nothing conn...

Crab apple maybe? I did watch a video on how to take it to bits, there is a fair amount of dismantlage required. The last time I took a laptop apart I broke the ribbon connecting the touchpad, and also the ribbon for the CD drive. I don't know how I did break the CD one, it just seemed to get trapp...

Alas I'm not too good on the BBC one, now the Dragon version I might stand a chance

Cheers.

Phill.

I haven't fitted the ramrom board yet, as I wanted to go one step at a time (for a change). The atom was fine with the atommc before. When I connect a PSU (4A 5v) it cuts out, but without a PSU connected, it measures 300 ohms across the power connector. Any suggestions, or a valid range of resistan...

I didn't have as much luck! (or skill?) I soldered mine near then end of the PL8 pins, but the lid didn't fit, sol I desoldered it and moved it further down them. I had to relocate my power connector to make room for my RAMROM board, which I did by removing the regulators and their heat-sink. And n...

Right Hotel booked, see you all in a couple of weeks.....

Cheers.

Phill.

Hi all, I've just managed to get the CPLD on my System floppy clone baord to work correctly with unmodified 3.5" drives so that it doesn't timeout, and requires no modification of the code. (basically added an extra flipflop to the timeout chain, which is easy to do in a CPLD). I may at some point t...

Thanks both for the replies, found it, the controller IC is way obsolete so need to find a new (Arduino ?) solution. I made a little PS/2 -> System keyboard adapter, just based on a single Mega328 compatible chip, will prolly get some boards made at some point. Not Arduino, but just standard AVR-GC...

Hi David, All, I'm the person that designed the RAM ROM board, and two of the versions of the colour board. The RAMROM board has been updated and I may have a spare that I can supply. The colour board situation is this: I Origianally designed a colour board that was based on the LMH1251, which I cal...

I think faulty RAM ICs is one of the most common faults on any machine of this era :) :) IIRC the XEGS I repaired for Arcadian had another fault I think that was the one where the 6502C has also failed. so made up a board to convert a standard 6502....basically a copy of the circuit from the origina...

Thanks all for the encouraging comments and help so far, I'll post progress here as it happens. I'm guessing it would be better placed on one of the other forums and not 'introduce yourself', would '8 bit' / 'hardware' be the best place ? I think we had a discussion a while back and it was suggeste...