The Jameco JE520 Voice Synthesizer

Jameco JE520 Voice Synthesizer for C64The latest acquisition is the JE520 by Jameco. This external voice synthesizer came in two variants: the JE520-CM for Commodore and JE520-AP for Apple II. The only difference was the interface connection to the computer. The Commodore version, the one I have, connects to the user port while the Apple II version connects via an interface slot card. Otherwise, I believe the rest of the hardware to be the same. I found an advertisement for it in RUN issue 7 1984— it retailed for $115-$150.
Jameco advertisement for JE520 in RUN magazine 1984
It’s based on the National Semiconductor Digitalker 54104 voice synthesis chip and four 2764 64kbit (8kbytes) EPROMs that form that vocabulary that it’s able to speak. This means it’s able to speak only using a fixed wordset. National also sold a series of vocabulary ROMs with the chip, but I believe this version has a custom ROM set from Jameco. It includes a built in amplifier and speaker with volume adjustment (located below) as well as a mini jack for sound output. Power comes directly from the computer.
Inside the Jameco JE520 Voice Synthesizer for C64
I didn’t receive a manual or software so it’s trial and error. At first, I assumed it would communicate with the computer over a serial interface since most devices that connect to the user port on a Commodore would use serial. And it would greatly simplify communication by using serial. But loading a terminal program resulted in the synth talking complete gibberish.

I later realized that it must be using parallel instead. And indeed, it does appear that way. The computer interfaces via parallel directly to the data pins of the Digitalker chip. On the Commodore, this is PB0 through PB7. So, it should be a simple matter in BASIC to get it to speak. So I tried the following program.

10 POKE 56579,255:REM PB0-PB7 OUTPUTS
20 FOR I = 0 to 255
25 PRINT I;
30 POKE 56577,I
40 FOR J = 1 to 350:NEXT J
50 NEXT I

After RUNing the program, the voice synth began speaking words after iteration 8 with “FAIL”, “FAST”, “FIRE”, “FIRST”, “FORWARD”, etc. (0-7 were silent). It kept speaking properly until iteration 127 when it began talking mostly gibberish again through 255 with an occasional “SECOND”.

I’ve found online that two folks have said that their ROM #2 has gone bad so I decided to dump them in the hopes that I have a good copy. Dumping ROM 1 went well, but ROM 2 seems like it’s going bad. It returns different data each time it’s read. ROM 3 and ROM 4 read fine. So, it appears I also have the same problem most others do. I’m hoping that someone reading this will have access to the ROM set so I can burn a good version and get the voice synth working properly again. I’d even like to try the original National Digitalker Voice Vocabulary ROM set as I’m thinking they should be compatible as well. Leave a comment if you’re able to assist.

An interesting bit of trivia about this device is it has origins that can be traced back to someone named Forrest Mozer. The chip even contains his last name on the top. Mozer was a co-founder of Electronic Speech Systems (ESS) and developed the lossy codec that’s used to encode the speech that’s stored on the ROMs. Apparently, he did most of the encoding himself, by hand! Mozer’s codec went on to give speech to C64 games like Ghostbusters and Impossible Mission, without additional hardware. The National 54104 Digitalker was also used in the arcade hit Berzerk.

Guest DJ Set On WVUD 91.3FM

I’ve been invited to have a guest DJ set for All Tomorrow’s Parties on WVUD 91.3FM in Newark, DE. It’s simultaneously exciting and terrifying. The theme is synthpop, new wave and the Fairlight CMI. I’ve attempted to put together some cuts that I enjoy myself while trying to weave some threads through the artists.

I’ll be on Tuesday June 23, 2015 from 7:00pm to 9:00pm EDT.

Commodore 1520 Plots .SVG Images

Commodore 1520 Plots SVG FilesI’ve put together a quick program that can convert an .SVG file into data statements that can be used to plot it on a Commodore 1520 Printer/Plotter. The program doesn’t run on the Commodore 64 (yet) but instead runs in the browser. It’s not ready to release yet as it’s fair picky about the types of .SVG files you feed it.

To whet your appetite, I’ve prepared a .D64 disk image that has four BASIC programs that will plot four different Commodore logos.

Download the disk image here.

And if you need plotter pens for your Commodore 1520 printer, you can get new old-stock pens from @futurewas8bit!

3D Visualization on the Commodore 1520

Riz1520_Plots00011Recently on the Lemon64 forum, user Rizthomas posted some excellent scans of some plots that he did on a Commodore 1520 Printer/Plotter back in 1986. The plots were well executed and very intricate. Some were 2D “string art” and some were 3D functional models. Unfortunately, Rizthomas was unable to locate the original disks for his plots (still hopeful they’ll turn up!) but was generous enough to point everyone in the direction of where he began.

One route was Transactor Magazine Volume 6, Issue 4 which contained a program called The Projector by Ian Adam of Vancouver, B.C. The program was of combination BASIC that built on top of a series of machine language routines (from Transactor Volume 5, Issue 6) that made it easy to draw lines, circles, and text on a hires screen. The routines were called with a SYS command from BASIC and were passed coordinates as variables. This made it incredibly easy to patch the program to also send those coordinates to the Commodore 1520 Printer/Plotter with a few modifications.

  • The hires screen coordinates (320×200) doesn’t match the 1520 plotter (480,999) but that’s easily taken care of by scaling the coordinates by a factor of 1.5.
  • The program includes several functions to plot contained in REM statements. I broke those out into a menu system so you can choose a function to plot.
  • I eventually matched Rizthomas’ color choices by making horizontal lines blue, vertical lines green, bounding box green and text black (on the plot only).
  • The origin of the plotter (current pen location at start) is (0,0). Below that point is the negative Y axis so you need to advance the paper up by 300 and then send the “I” command which sets a new “relative origin” point. Now the coordinate systems match screen coordinates (bottom left is (0,0)). Sending the command “R” instead of “M” for moving (pen up) will now use the new relative origin as does “J” instead of “D” for drawing (pen down). The 1520 manual is a great resource to understand the coordinate system of the plotter.

3d 1520 plots

You can download the program (and required ML program) here.

The nice thing about the program is that it will draw a line on the screen while drawing it on the printer simultaneously so you can see both evolve together. Enjoy and a big thanks to Rizthomas for the pointers to the code! If you’re able to get it working, let me know in the comments (and let’s see what you plotted).

Here’s a quick Vine of the plotter working:

Using Prowl to Announce IP Address of Raspberry Pi on iOS

Prowl on iOSIf you use your Raspberry Pi without a keyboard and monitor, you know how frustrating it can be to use it without knowing it’s IP address. By default, the Raspberry Pi is configured to use DHCP to obtain an IP address. This is great for moving the unit around to different networks but can be annoying when you want SSH to the unit. Typically you can use the zero-config/Bonjour “raspberrypi.local” address but this doesn’t always work. I’ve instead come up with a way to use Prowl to notify me of the current IP address after it boots. As a bonus it works with either an Ethernet or WiFi (or both) connection.

Prowl is a Growl push notification service for iOS. It costs $3 and is available from the iTunes App Store.

1. The first step is to download and install Prowl and setup an account. Next, obtain an API key from Prowl. Copy the API key– you’ll need to insert it into a script below.

2. Next, create two files in your home directory (/home/pi/) called prowl.sh and prowlip.sh. Insert the API key into prowl.sh as shown.


File: prowl.sh from koma5 on github.

#! /bin/sh
# Usage: ./prowl.sh priority(-2 to 2) app event description
# Example: ./prowl.sh 0 "transmission" "torrent has finished" "Coen Brothers Compilation has finised downloading"
app=$2
priority=$1
event=$3
description=$4
apikey=PASTE_YOUR_HEXADECIMAL_API_KEY_HERE

if [ $# -ne 4 ]; then
echo "Usage: ./prowl.sh priority(-2 to 2) app event description"
echo 'Example: ./prowl.sh 0 "transmission" "torrent has finished" "Coen Brothers Compilation has finised downloading"'
else
curl https://prowl.weks.net/publicapi/add -F apikey=$apikey -F priority=$priority -F application="$app" -F event="$event" -F description="$description"
fi


File: prowlip.sh with apologies to original author.

#!/bin/sh

eth=`ifconfig eth0 | awk -F':' '/inet addr/&&!/127.0.0.1/{split($2,_," ");print _[1]}'`
wlan=`ifconfig wlan0 | awk -F':' '/inet addr/&&!/127.0.0.1/{split($2,_," ");print _[1]}'`

if [ "x$eth" = "x" ]; then
eth=""
# Variable is empty
else
eth="eth0: $eth "
fi

if [ "x$wlan" = "x" ]; then
wlan=""
# Variable is empty
else
wlan="wlan0: $wlan"
fi

/home/pi/prowl.sh 0 "Raspberry Pi" "IP Address" "$eth$wlan"


3. Set both files to executable by typing

chmod 755 prowl.sh prowlip.sh

4. Add this line to /etc/rc.local before the “exit 0″ line. This will execute the script at startup.

/home/pi/prowlip.sh

5. Reboot your Raspberry Pi and you should receive a push notification from Prowl on your iOS device with the current IP address(s).

DIY RS-232 Interface for Commodore C64 for under $15

If you have a Commodore 64, chances are you’ll eventually need to connect a modem or other serial device to it. You’ll find that’s not quite that easy since the C64 doesn’t have a standard RS-232 serial port. What it does have is called the “user port” and it can do serial over this port but it needs to be changed from TTL levels (0 to +5v) to RS-232 levels (-15v to +15v).

If you’ve ever attempted to purchase a VIC-1011a terminal type, SwiftLink or Turbo232 from eBay you’ll quickly find out that the price gets out of hand. Expect to pay upwards of $100 or more for these adapters.

Luckily, there’s an inexpensive way to get a RS-232 port on your C64 and it’ll cost you less than $15. Ready?

You’ll need these parts for the project.

Connect the RS232-TTL module directly to the C64 user port edge connector using the table below.

RS232-TTL Module C64 User Port
GND A & N
TXD M
RXD B & C
VCC 2

Update! Alwyz from 1200baud suggested that connecting VCC isn’t necessary and potentially dangerous. I’ve had zero problems with mine as listed here. I’m providing this warning so you can make your own decision!

C64 RS-232 Adapter

Observe which side of the user port connector is the top (it’s the one with numbers– letters are on the bottom). It’s helpful to write on it with marker. For wire I used female jumper wire that I cut one end off. For GND and RXD you’ll need to jumper two of the pins together on the user port connector. I used a small bit of CAT5 solid core wire.

Once you’ve got it connected, add the null modem adapter and connect your modem. You may need to also use a gender changer and/or a 9 pin to 25 pin adapter depending on your modem.

Fire up CCGMS, Novaterm or Striketerm, set the baud rate to 2400, set the port to the user port and give it a few “AT” commands. You should see “OK” being returned. If it doesn’t, make sure you have a null modem adapter (test it on another machine to confirm) and double check your connections.

As with any tutorial you find online, be responsible and double check my work and your work before proceeding.

How to get software to disk for your Commodore 64

Commodore 64It’s a question that pops up from time to time on forums from Lemon64 to Reddit C64.

“Yes! I just got a Commodore 64!! Now how do I get disk images onto disk so I can do something?”

It’s not straight forward. Folks in the Apple II world have a fantastic program called ADTPro that can work over a simple audio cable connected to your laptop headphone and microphone jack (or serial). Doesn’t get any easier than that.

On the Commodore, disc images are stored in .D64 format which is an image of a standard 1541 floppy. Most software you find is available this way. You may also find .D71 and .D81 which are for 1571 and 1581 formats but these are less common. A great place to find C64 software is the CBM8BIT.com Search. Once you have your disk images, you’re ready to make some floppies. Below are some of the options to “burn” disk images for your Commodore 64.


uIEC/SD2IECuIEC/SD2IEC ($50-60) is probably the easiest overall solution. With this small device, you can load .D64 images from your Mac or PC onto a SD card. Inserting into the uIEC, it will show up to the C64 as an extremely large volume. But merely having a .D64 image doesn’t get you very far– you need to “burn” the image to a real floppy. Fortunately, there’s D64it which can do just that. It’s a little slow as the author admits, but it gets the job done. Things are sped up considerably if you have the JiffyDOS ROM ($20) installed in your C64 since the uIEC is JD compatible. Don’t forget a 6-pin IEC cable!


64NIC+64NIC+ ($50-59) adds Ethernet capability to your Commodore 64 as well as a ROM socket that can accommodate up to 256kB ROMs. With networking capability, now you’re able to use WarpCopy64 which can upload and download entire disc images to your PC. There’s a bit of a chicken and egg problem here since you’re going to need WarpCopy64 on disk first before you can create new disks.


ZoomFloppyZoomFloppy ($35) is a great solution to connect your Commodore 1541 to your Mac or PC via USB. ZoomFloppy is a modern version of the “X” series cables which required an old PC with a parallel port plus knowledge of IRQ and ports (see below). After installing OpenCBM software on your Mac or PC, you can read and write D64 images quickly and easily– no fuss. Hands down, this is my preferred way to read and write floppies.


If you’re lucky to have a terminal program already on floppy on your C64, you can do the serial route. Of course, you’ll also need an adapter that plugs into the C64 user port to give you standard RS-232 signals. These can be difficult to come by if you don’t have one, like the Commodore made VIC-1011a. One could also build this USB to RS-232 interface for your C64 for $15.


If you have a PC that’s old enough to have a parallel port on the motherboard, you might have good luck with “X” series parallel cables. These cables connect your parallel port to the IEC port of a 1541. From there, you can run Star Commander in DOS mode to read and write files and images. I started using this method years ago but abandoned it for the ZoomFloppy.

So there you have it. There’s no shortage of solutions and every solution is most likely going to cost you something. But each is a great investment and keeps the scene going with folks creating new methods. This list isn’t exhaustive– if you know of one or have experience with any of these, leave a comment!

Reddit r/retrobattlestations Commodore 64 Port


For the next two weeks, it’s BASIC Week 2 at Reddit r/retrobattlestations. You can participate with your Commodore 64 or at least play along with your favorite emulator. I’ve ported the code to the C64 and you can get the code from the thread on Reddit. Or you can download the D64 image here to make your own disk or to use with an emulator like VICE.

Have fun!

The PP&S Frame Grabber 256 for Amiga

The Frame Grabber 256 by Progressive Peripherals and Software (PP&S) is a video frame digitizer capable of capturing a single frame from moving video in up to 256 shades of gray. There was also a color version simply called Frame Grabber. I owned the color version in the late 80’s/early 90’s but eventually sold it to fund other things.

A few years ago, I won an eBay auction that was a Commodore grab bag. Among the items was the Frame Grabber 256 hardware box but nothing else. It was missing the manual, the software and the power supply. My search for these items came up cold and I shelved it.

The unit is very interesting since it can drive an Amiga monitor natively and display the NTSC video through it, without the aid of the computer to process it.


Recently, my interest was renewed so I began looking again and I struck gold. I’ll share the wealth with you below.

The pin numbers/layout are wrong. The position and values are correct.

It’s important to note the power supply and the pin-out that’s printed on top of it uses a numbering scheme in the diagram that is very wrong. The locations and their corresponding values are correct though. When you go searching for a suitable power supply, you’ll need to use the following.

  • Pin 1: COM
  • Pin 2: GND
  • Pin 3: +5v
  • Pin 4: -12V
  • Pin 5: +12V
  • The correct pin layout:



Instead of purchasing a new power supply, I created an adapter cable for an ATX power supply. I used the table below for the connections.

  • DIN Pin 1 to ATX Pin 13
  • DIN Pin 2 to ATX Pin 3
  • DIN Pin 3 to ATX Pin 4
  • DIN Pin 4 to ATX Pin 12
  • DIN Pin 5 to ATX Pin 10

You can get a 3 pack of 3ft MIDI cables for the DIN portion for $1.97 at Radio Shack. They will price match in the store. It’s an unusual bargain. Unlike most MIDI cables, these have all five pins connected.

It goes without saying, I’m not responsible for any damage that may succumb to your gear. Double check everything with a second source!

Moment of truth came and I connected it to my Amiga 4000 via a parallel cable, and connected a small point and shoot digital camera that has an NTSC video out cable. Success! There’s some tearing in the image along the way that might be caused by a bad video cable but otherwise it looks like it’s working.

Make an Apple // disc for BASIC week at Reddit RetroBattlestations

Apple //e for BASIC weekBASIC week at Reddit /r/retrobattlestations is over but you can relive the fun on your Apple // without any typing! Simply follow these steps to download the disk image to a new disk for your machine.

  1. Connect your laptop, tablet or phone’s headphone jack to the tape input jack on the back of your Apple // using a 1/8″ mini headphone cable.
  2. Turn the volume up to maximum.
  3. Turn on your machine and hold control and hit reset to get to a ] prompt.
  4. Insert a blank disk into drive 1 (it will be erased!).
  5. Turn on caps lock and type LOAD and hit return.
  6. Begin playing the .WAV file below on your device.

If all goes well, in about 2 minutes you should have a floppy that you can now boot from. When it’s finished, hit return to reboot your machine. ProDOS should load BASIC. Once it does, type LOAD REDDIT and then RUN.

[Apple // .WAV file to disc for BASIC week program 5.5MB]

Credit for creating the .WAV file from a .DSK image goes to C2T found at ASCII Express.

Enjoy!