Sidewise ROM board

Today I received my latest BBC Micro-related purchase, an ATPL Sidewise ROM board:

ATPL Sidewise ROM board

I decided to fit this board to the BBC Micro with the RetroClinic Datacentre installed in it, however fitting this board was not as easy of a task as I had initially anticipated.

Problem #1: The power supply

The Sidewise board requires that the power connectors be bent at a 90 degree angle in order to make room for the board. This was not a problem in the past, as the spade connectors of past power supply revisions used a softer plastic/rubber connector which could be bent easily, however newer power supplies use a hard plastic connector. Thankfully, the instruction manual that came with the unit came with an addendum covering this scenario. The solution is to cut a notch into the spade connector and carefully bend it round. The manual with the instructions on this process, as well as general fitting instructions, can be found on Retro-Kit’s website here.

Problem #2: CombiROM

The next problem came when I booted up the machine for the first time. I was greeted with a message that simply said ‘Language?’, meaning that the system cannot find the BASIC language ROM.

After some further testing, I narrowed the problem down to the use of the RetroClinic CombiROM for the language. From what I’ve found online, it seems that this ROM contains the BASIC language and ADFS. I believe it also contains RamFS, but there is a second chip installed which is labelled ‘CombiUtils/RamFS’, which I believe is what the Beeb uses for RamFS. I swapped out the CombiROM for a standard BASIC language ROM salvaged from an old BBC Micro (now used for parts), and the system booted up into BASIC. RamFS is being picked up in the socket corresponding to the CombiUtils/RamFS chip, but no ADFS.

My theory is that the Sidewise board cannot handle this combination of ROMs in one chip, but I could be wrong. I believe that I can get ADFS back by fitting the CombiROM chip back into one of the on-board ROM sockets, however I haven’t tried this yet.

Update (7 May 2017): No joy with installing the CombiROM chip into the on-board ROM sockets. After switching into DFS using the *DISC command, typing *XADFS causes the Beeb to hang.

Update (5 June 2017): I have managed to re-gain access to the ADFS drive by burning a copy of ADFS 1.33 to an EPROM and installing it in the system. Hooray!

Ch-Ch-Cheese Wedge

Today I received an item that I have always wanted for my still-young Acorn computer collection:

I purchased this towards the end of January 2014. The only problem is it seems that one of the capacitors in the power supply has blown, as the seller said he plugged it in and it started emitting horrible electrical smells. This is similar to what happens to a lot of BBC Micros after around 20-30 years. Replacing the capacitors in the Beeb’s power supply is something of a rite of passage for an Acorn collector, so I’m hoping that it’s a similar problem with this 6502 second processor. The theory goes I should be able to get it working again by changing the capacitor which failed in the same way that one does to a BBC Micro.

I briefly opened up the processor to see if there was something glaringly obvious wrong with the power supply, but this first glance of the processor proved inconclusive. There is definitely quite an unpleasant smell reminiscent of a failed BBC Micro power supply, though. If all else fails, I believe that these can be run with a BBC Micro power supply, but ideally I want it to all still fit in the original box.

Disc fault 18 woes

Yesterday, I received a Pace 5.25″ floppy drive for my Beeb. When I plugged it into my Beeb and tried to format a disk with *FORM80, I was greeted with the message:

“Disc fault 18 at :0 00/00″

I opened up the drive, and watched it in operation with the cover off. It looks like the disk is spinning, but it doesn’t seem to do much else.

I then tried another floppy drive that I had, an unbranded 5.25” floppy drive and was greeted with the same error. This drive made a rather concerning grinding noise when I tried to *CAT the disk.

The only common thing between the two floppy drives is that they are both powered by the Beeb’s auxiliary power port. I’m thinking that the drives might not be receiving enough power. The Pace drive uses a standard Molex power connector inside, so I’m going to try hooking up a PC power supply to the drive and seeing if it works when externally powered.

(Long-overdue) Update (May 13 2017): I believe the problem may be as simple as the heads on the drive are dirty. I am going to give them a clean and see what happens.

Econet upgrade fitted

Yesterday, I finally got round to fitting the BeebMaster Econet upgrade I bought for my Beeb (number 3 on the “My Micros” page). The process was fairly straight-forward, with most of the time spent on trying to find R46 on the motherboard! This was my first time soldering something outside of practice, so some of the solder joints looks a bit ropey, but it looks like contact is being made on each of the joints, so it should be all good.

I haven’t yet plugged the Beeb into the TV since fitting the upgrade, as I finished at 10.30pm last night and had an early start in the morning. I did, however, plug it into the wall and power it on briefly. The Beeb responded with a “BEEEEEEP-bip”, so it’s looking good.

Edit: It’s alive! I plugged the Beeb into the TV, and pressed N+Break and it came up with “Econet Station 128 No Clock”, so it looks like the upgrade was a success! I won’t be completely sure until I can get the Beeb hooked up to an Econet (which won’t be for a while), but it’s looking promising.