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Knitwear Designer for the BBC Micro, project part 1


nitwear Designer from Database Publications, written by Kendall Down.

Some time ago I discovered and bought this software. It allows you to design a jumper or other knitwear; give it some sizes and your knitting gauge, and it gives you a knitting pattern. I believe it works on the Electron as well as BBC and Master, but I don't have a disc drive for the Electron. In the following pictures I'm using it on a model B+. 

The disc worked, the only issue was that it sends its output to the printer.  If you're knitting the garment then you really do want the pattern on paper.  Frustratingly I gave away a Centronics dot matrix printer just a couple of years ago, slimming down for a house move. It's not the kind of thing I really want to give space to again. Is it possible to connect a modern printer to a BBC via RS232?  I'm not sure.  If it's possible to save the output as a text file and recall it and read it off the screen, then I suppose that might work.  If that's possible, I couldn't find out how to do it [1].  
It is of course possible to use this software in the Beebem emulator and capture the print output as a text file. But I wanted to use my disc and original hardware as far as possible. I considered hooking up the BBC to a modern computer via serial to USB to capture the print output but the idea of using my RC2014, a Z80 kit computer, appealed to me and seemed appropriate.

I already had the RS232 kit for my RC2014. This seemed like a good solution, and a way for me to learn a bit more about serial communication. I could write a program for the RC2014 to save the data to a file, or just echo it to the screen and copy and paste it from the terminal program.  I had to add an enhanced clock module to my RC2014 which allows me to set the clock speed and therefore match its baud rate to one of the baud rates offered by the BBC.  I also had to make up a special lead to connect the BBC's serial port (an unusual 'domino' 5-pin DIN) to an RS232 plug.
Here's the program running. You can choose from a couple of standard jumper styles, or get creative with a freehand tool. I believe that lets you draw pattern pieces on a grid and gives you the knitting pattern. But that's for another day.  I went for a straightforward raglan jumper. First it asks you lots of questions about the required measurements and your knitting gauge (the factors involved there are your yarn and needle thickness as well as your personal knitting tension). 
For knitters, this raglan jumper is made in flat pieces and has ribbing at the waist and cuffs. As you can see, the pattern gives you X stitches and Y rows "in pattern" which allows you to knit plain, in Fair Isle colourwork or a stitch pattern. I went for a gauge of 4 stitches per inch and a stitch pattern that has an 8-stitch repeat, and that seems to have worked out perfectly. 
Here you can see that although it does send its output to the screen as well as to the printer,  it's difficult to read, and as I mentioned, I'm not sure whether it's possible to save and recall it. Here is the first part of the pattern, as received by the RC2014 (I wrote a simple program to receive the characters and echo them to the screen).

Here is the jumper I want to re-create. It's an old friend; it fits like a glove and is very comfortable. I added an inch to the body length because I like a longer jumper. Also pictured is my pattern, and the swatch I made, trying out a stitch pattern similar to the one the jumper has, and to find a rough gauge. (When I buy or spin my yarn for the project jumper, I'll adjust needle size to get the gauge that I gave the program.)  I'll make a pink jumper, like the one I'm copying. The teal yarn is just what I happened to grab to make the swatch. 

I'm not a fast knitter! Once I have the yarn it'll take a while to make the jumper.

[1] There's a disc in the box, but no manual. I'm pretty sure I found a manual for this software offered online once, but I can't find it now. 


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