New NC200 User Questions

pollito · 21:21, 16 June 23

Hi there,

I bought an Amstrad NC200 a short while ago, and have just managed to get it up and running with a universal power adaptor (I had to cut the wire to reverse the polarity but I lucked out on the tip size).

It's in good condition, but I just have a couple of questions, and was hoping somebody could help:

1. When I first power the machine on, the screen seems to only be working in a single square around 4/5 of the way in. I thought it was because my power supply is slightly overvoltage (7.8V), but it happens when I lower the voltage to 6V too. After I press the On/Off button once or twice this clears. Has anyone else had this issue and, if so, is it anything to worry about? Can it be fixed?

2. The floppy drive has life but won't read/write any floppies (I have tried 3x single density that all work fine in my Risc PC). If I try to format one, I hear a noise that sounds like an electric shaver, and after a few seconds I'm told that there is no disk in the drive. Does this sound like the drive belt has gone? If so, where can I buy one, and how easy are they to replace? Also what are my other options? I saw someone had fitted a Gotek but that might be beyond my current ability. I will be getting a 1MB SRAM card in a few months, but I'm not sure how I would get data onto the NC200 from my PC. Could I transfer over serial? I would like to run CP/Mish or maybe ZCN.

As always, any help is greatly appreciated!

Nick

Sykobee (Briggsy) · 23:05, 18 June 23

1. I haven't had this.

My NC200 has a rechargeable battery mod, but I'm using an aftermarket power adapter too.

2. I need to try the floppy drive (seriously!) and get the SRAM card, but I'm kinda stuck finding a use for the machine. I was thinking of maybe a funky infocom adventure terminal with cp/m-ish. But I wouldn't be surprised if the belt had gone - as it's a 3.5" drive i'm sure the belts are easy to source and replace. But I'd go for the Gotek myself (but again, for what purpose?)

There is a serial terminal program on the NC200. I did watch a guide to cp/m-ish on youtube - it has a driver for larger,cheaper PCMCIA drives. I wonder if it would be possible to rom-hack the NC200 ROM to improve PCMCIA functionality. It's such a niche device though.

zgedneil · 10:31, 19 June 23

On an NC200 without a memory card or floppy disk, ZCN can be transferred over a serial link and used with just a 45k (!) ramdisk. Make sure you get ZCN 1.4 though. It's certainly not the ideal way to use it, but it does work, and you could use things like pmarc and ZX0 compression to make better use of the space.

pollito · 20:43, 20 June 23

Quote from: Sykobee (Briggsy) on 23:05, 18 June 231. I haven't had this.

My NC200 has a rechargeable battery mod, but I'm using an aftermarket power adapter too.

2. I need to try the floppy drive (seriously!) and get the SRAM card, but I'm kinda stuck finding a use for the machine. I was thinking of maybe a funky infocom adventure terminal with cp/m-ish. But I wouldn't be surprised if the belt had gone - as it's a 3.5" drive i'm sure the belts are easy to source and replace. But I'd go for the Gotek myself (but again, for what purpose?)

There is a serial terminal program on the NC200. I did watch a guide to cp/m-ish on youtube - it has a driver for larger,cheaper PCMCIA drives. I wonder if it would be possible to rom-hack the NC200 ROM to improve PCMCIA functionality. It's such a niche device though.

1. I'm fairly sure this is a capacitor issue as there is a hissing sound, and the issue clears up on its own after a few seconds if I don't power cycle. Unfortunately I can't find a list of capacitors to order from anywhere so I'll probably have to check when I fix the floppy drive.

What is the rechargeable battery mod? I was looking at rechargeable size C batteries and they're ridiculously expensive. Also the NC200 takes 5 and you can only charge 2 at a time in my charger! Would be great to be able to charge it like a modern laptop.

2. Maybe this would be a good use once it's finished

At the moment my NC200 is out-of-the-box as far as upgrades go, but I'm enjoying using BBC BASIC. I want to learn Z80 assembly, and BBC BASIC has a built-in assembler. I would very much like to run one of the CP/M OSes because there's a lot of software available.

As far as I am aware, standard 3.5" drives don't use belts, and I'm trying to find one myself now. I read somewhere they should be 2mm thick. I just measured the ones in my drawer and they are all 2mm thick, and of varying lengths, so hopefully one will fit. I looked at the Gotek solution for the NC200 but it seems too destructive to the case for my liking. Any hack I do to my vintage hardware I like to be reversable. I'm sure collectors in 100 years time will be swearing at us for what we've done to these machines in the present!

I have two 1MB PCMCIA cards from this guy for $15 each, but he point blank refused to send them to Europe so they are currently with a colleague in the US who will bring them over next time he visits his family in the UK. Should make a good Christmas present.

pollito · 20:51, 20 June 23

Quote from: zgedneil on 10:31, 19 June 23On an NC200 without a memory card or floppy disk, ZCN can be transferred over a serial link and used with just a 45k (!) ramdisk. Make sure you get ZCN 1.4 though. It's certainly not the ideal way to use it, but it does work, and you could use things like pmarc and ZX0 compression to make better use of the space.

Thank you so much for this info, I had no idea! Unfortunately I left my serial cable back in the UK but will see what I can cobble together. Is it just standard null modem cable?

zgedneil · 09:43, 21 June 23

If you have a serial port available already then yes, it should be just a standard null-modem cable that you need. (But often nowadays you would be needing a USB-to-serial converter too.)

Prodatron · 14:48, 23 June 23

Some more questions:

- New power supply:
seems that I lost my NC200 power supply or never had one. The same for my NC100. Regarding the NC200, can I just use any 7,5V, 1A DC PSU and swap the +/- or is there something special I have to take into account?

- PCMCIA SRAM card:
today I received an PCMCIA 1MB sram card. As it's battery backed maybe it's possible to transfer some stuff (like an executable binary) onto it with my PC when using an adapter?

- And how does the NC handles files/data on the 1MB external ram at all?

Any hints are welcome!

zgedneil · 22:42, 23 June 23

I think a bootable memory card is just left alone by the ROM OS storage-wise, but I could be wrong. I don't think I ever looked much at what the ROM does with it beyond that, but it might be similar to the format used for the "upper memory" storage, which seems to be a custom FAT-based scheme. (ZCN's "rrxfer" can read files from that in a RAM snapshot.) ZCN just uses a very basic 256k CP/M format, with as many drives on the card as fit.

pollito · 17:22, 25 June 23

Quote from: zgedneil on 09:43, 21 June 23If you have a serial port available already then yes, it should be just a standard null-modem cable that you need. (But often nowadays you would be needing a USB-to-serial converter too.)

Many thanks. My recently acquired PCs are old enough to have them so I will make up a null modem cable.

pollito · 17:26, 25 June 23

Quote from: Prodatron on 14:48, 23 June 23- New power supply:
seems that I lost my NC200 power supply or never had one. The same for my NC100. Regarding the NC200, can I just use any 7,5V, 1A DC PSU and swap the +/- or is there something special I have to take into account?

I bought a standard universal power supply, swapped the + and -, and set it to 7.5V. It works fine for me.

News:

New NC200 User Questions