eBay Oddity: Silver Reed EB-50

Silver Reed EB-50 PrinterToday I present to you the Silver Reed EB-50. Made in 1985, this thing has a bit of an identity crisis. It’s a printer, a plotter and a typewriter all in one. The reason I got it was because it uses the same tiny ball-point pens that the Commodore 1520 printer/plotter uses. However, this prints on normal 8.5″ wide paper. It’s also very portable, has a lid that covers the keyboard and a flip out handle. It can run on batteries (5 x D cells OMG heavy) or on DC 7.5V power (center negative in case you want to know). For $9.99 it was a bargain curiosity that I couldn’t pass up.


In normal typewriter mode, you press a key and it will “draw” that character in one of 3 sizes, styles or directions in one of 4 colors. You can position the print head anywhere you’d like to print text. In addition, there are function keys to create graphs, right on the typewriter. Pie charts, bar graphs and line graphs are simple– select the type, enter the data points and it prints a graph at the print head position. Pretty clever for something that works sans computer.

Switch it to printer mode and now a computer takes over via the parallel port. This is where things got weird. I found reference to someone that wrote a program to convert HPGL plotter files to ones that printed on this one. This was key since there was no manual and I ran out of internets. But the file was locked up in a “drivers” ad supported nightmare of a website that had me install some bullshit driver manager on Windows to “install” a C code source file. What-fucking-ever. It’s included below in you want it.


A quick Processing sketch later and I’ve produced some output on it from my Mac using an old PowerPrint serial to parallel adapter via a KeySpan USB to serial adapter. Lots of adaptation, but what do you expect from a nearly 26 year old printer.


# hp2eb50.c
#include <stdio.h>

#define SCAL(x) (((x)+halfscale)/scale)
#define NUMV(x) ((x)=='-' || ((x) <= '9' && (x) >= '0'))
#define SP ('S'<<8)+'P'
#define PU ('P'<<8)+'U'
#define PD ('P'<<8)+'D'
#define PA ('P'<<8)+'A'
#define IW ('I'<<8)+'W'
#define SC ('S'<<8)+'C'
#define LB ('L'<<8)+'B'

FILE *source, *plotter;
short c,i,j,pen,scale,x1,x2,y1,y2,hx,hy,halfscale;
short befehl,ende,rot, colour[] = {0,1,2,3,0,1,2,3};
char param[100], *output;

void upcase(s)
   char *s;
  {
   register char c;
   register int  i=0;

   while ((c = *(s++)) && i<99)
     {
      param[i++] = (c>='a' && c<='z')? c-'a'+'A' : c;
     }
   param[i] = 0;
  }

short get_num()
  {
   register short c,x=0;
   short s;

   if (ende) return(0);
   else
     {
      while(((c = getc(source)) & 0x1ff) <= ' ');
      if (c == '-')  
        {
         s=-1;
         c = getc(source);
        }
      else s=1;
      while (c >= '0' && c <= '9')
	{
	 x = x*10+c-'0';
         while(((c = getc(source)) & 0x1ff) <= ' ');
	}
      if (c == ';') ende = -1;
      return(x*s);
     }
  }

void rotate()
  {
   register short h;

   if (rot)
     {
      y2 = y1;
      h = x1; x1 = y1; y1 = -h;
     }
  }

main(argc,argv)
   int argc;
   char *argv[];
  {
   if (argc<2)
     {
      printf("Usage: %s <hpgl-file> [SCALE <scale>] [ROT] [COLOUR <n1..n8>] [TO <output filename>]n",argv[0]);
      exit(0);
     }

   rot = 0;
   output = "par:";
   for (i=2;i<argc;i++)
     {
      upcase(argv[i]);
      if (!strcmp(param,"ROT")) rot=1;
      if (!strcmp(param,"SCALE") && i<argc-1)
	{
	 scale = atol(argv[++i]);
	 if (scale == 0) scale = 1;
	}
      if (!strcmp(param,"TO") && i<argc-1) output = argv[++i];
      if (!strcmp(param,"COLOUR") && i<argc-1)
	{
	 for (i++,j=0;j<8;j++) colour[j]=(argv[i][j]-'0') & 0x03;
	}
     }
   halfscale = scale/2;

   if (!(source = fopen(argv[1],"r")))
     {
      puts("Sorry - Can't open file!");
      exit(0);
     }
   if (!(plotter = fopen(output,"w")))
     {
      puts("Sorry - Can't open output file");
      fclose(source);
      exit(0);
     }

   pen = 0;
   fputc(18,plotter);  
   puts(" Command no.:");
   j = 1;
   do
     {
      i = ende = 0;

      do
	{
	 c = getc(source);
	} while (((c < 'A') || (c > 'Z')) && (c != -1));
      befehl = (c==-1)? 0 : (c & 0xff)<<8 | (getc(source) & 0xff);

      printf("2331A23313C %5dn",j++);   

      switch(befehl)
        {
         case SP : {
		    x1 = get_num();
		    if (x1)
                      fprintf(plotter,"C%d;n",colour[(x1-1)&7]);
                    break;
		   }
         case PU : {
         	    pen = 0;
		    break;
		   }
         case PD : {
		    pen = 1;
		    break;
		   }
         case PA : {
		    while (!ende)
		      {
		       x1 = SCAL(get_num());
		       if (!ende)
			{
		  	 y1 = SCAL(get_num());
			 rotate();
		         if (pen==1) 
                             fprintf(plotter,"D%d,%d;n",x1,y1);
		           else 
                             fprintf(plotter,"M%d,%d;n",x1,y1);
			}
		      }
		    break;
		   }
	 case LB : {
		    fputc('P',plotter);
	            while((c = getc(source)) >= 32) 
		      putc(c,plotter);
		    putc(13,plotter);
		    putc(10,plotter);
		    break;
		   }
         case SC : {
		    x1 = get_num();
		    if (ende) break; 
		    x2 = get_num();
		    y1 = get_num(); y2 = get_num();		    
		   }
         case IW : {
		    if (befehl==IW)
		      {
		       x1 = get_num(); y1 = get_num();
		       y2 = get_num(); y2 = get_num();
		      }
		    hx = (x2-x1+999)/1000;
		    hy = (y2-y1+999)/1000;
		    hx = (hx>hy)? hx : hy;
		    if (scale<hx)
		      {
		       scale = hx;
		       halfscale = scale/2;
		       printf("New scale: %dn2331A",scale);
		      }
		    rotate();
		    fprintf(plotter,"M%d,%d;nI;n",SCAL(-x1),SCAL(-y2));
		   }
        }
     } while (c!=-1);
   fputc(17,plotter);
   fclose(source);
   fclose(plotter);
   puts("nReady.n");
  }

 

Testing a Geiger Counter Kit

I recently purchased a Geiger counter kit from Goldmine Electronics. I soldered everything together; attaching the Geiger tube was the trickiest as it’s not actually soldered to the board, just ”
strapped” with some wire in three places. One end of the tube is the positive (+) side and the entire center of the tube is negative (-).

I turned it on but couldn’t think of anything to test it with. It would occationally click every now and then but that’s normal background radiation. Then I remembered I had this bowl in the cupboard. I knew the the old 1930’s Fiestaware red/orange color was radioactive because they used uranium oxides in the glaze. This bowl isn’t Fiestaware but it’s probably just as old.

I won’t be eating from it again.

Print from iPad to ImageWritter II


What if you could print from and iPad to an ImageWriter II? Okay, maybe you don’t want to, but it was an exercise that ultimately proved to be fairly simple.

First, you’ll need a USB to serial adapter and the appropriate cables. I was lucky to have a Keyspan “USA-28X” 2-port adapter with 8-pin DIN jacks, just like the ImageWriter has. I suppose any serial port (9 or 25 pin) would work as long as you had an appropriate cable with 8-pin DIN on the other side. (You may also need to “null modem” the connection this way– not sure).

Next, you’ll need some drivers. Lucky for me, there’s updated drivers for 10.6 available at http://www.linuxfoundation.org/collaborate/workgroups/openprinting/macosx/imagewriter. Download and install the drivers for the ImageWriter II as well as GhostScript (this acts as the RIP to go from PDF to raster images for the printer).

Then you need to configure the printer. By default, the drivers install a print driver for every serial device on you computer. I chose to delete them all and add only one to prevent the clutter. I deleted the extra printers in the Printers Preference Pane. To add the ImageWriter II printer, browse to http://localhost:631/admin which will let you access CUPS on your machine. Go through the add printer procedure, choosing the right serial port, 9600 baud, 8,n1 and hardware flow control (match this to the DIP switches of your printer). Don’t forget to turn on printer sharing and to “share” this new printer!

Finally, you need to download and run AirPrint Activator 2.0 to enable AirPrint on your shared printers.

If all worked, you should see a new printer listed on your iPad (or iPhone/iPod Touch) and relive the sound of the 80’s all over again.