I put it together as a tribute to the old Popcorn service in Northern California. You could dial POPCORN from any phone, and a recording would tell you the time of day.
Originally, I wanted to use Joanne Daniels' voice (she was the voice of Popcorn), but I couldn't get enough samples of her saying all the numbers. Pat Fleet (the lady that says "A, T, and T") actually offers recordings, but you have to pay for them. So I settled on using my voice, and it's easy to substitute your own.
First, a little demo, then flip to the next page and I'll show you how to make it on a breadboard.
Step 1: FAQ
Audio samples are stored on an SD card. The time is tracked with the DS1307 RTC. The microcontroller polls the RTC every second to update the display and watches the big red 'announce' button. Once you hit the button, the microcontroller plays the appropriate samples based on the current time.
Q: How do I use my voice?
You just record your voice and copy to the SD card. I'll show you how in a bit, but it's easy.
Q: Can I make it do x
Probably. You can download the code on the next step - you can poke through it and change things fairly easily.
Q: What are the technical details?
It's a Parallax Propeller running at 80Mhz connected to a DS1307 Real-time clock and an HD44780 8x2 Character LCD (4-bit interface). The Propeller manages everything including audio playback using rayman's excellent wav playback objects. 16kHz mono or stereo wav playback is supported.
Here's a walkthrough of how it works. Note that I'm using an LCD UI module and Propeller Platform SD, but this instructable will show you how to build it with a breadboard.
Step 2: Materials
First I'll show you how to build your clock on a breadboard - and here's what you'll need for that;
Here's the sourcecode. Everything is available under the MIT license.
SD card slot
I mounted mine on a protoboard and cut to size with a dremel. I'm using a slot from mouser, You can also solder to the pads of one of those microSD - SD adapters. I've put mine on a protoboard to make it easier to connect.
8x2 Character LCD
Displays the time. Sparkfun has a 16x2 LCD that will work, too
I ripped this out of a little stereo set I had. You can also use a headphone speaker
3xAA battery box
Available at Parallax
Mouser Part #700-DS1307N
Available at Parallax
32.768 KHz Crystal
Mouser Part #73-XT262
Mouser Part #579-24LC256-I/P
Available at Parallax
5x Tactile Switches
Mouser Part #653-B3F-1000
3.3v Voltage Regulator
Mouser Part #511-LD1117V33
Around 10 10k ohm Resistors
4x 4.7k ohm Resistors
3 or 4 .1uF Ceramic Caps
3 47uF Electrolytic Caps
A Prop Plug
If you want to add a battery backup to the RTC, you'll need either a 3v battery, or a super cap and diode
Breadboard and a bunch of hookup wire.
An SD or microSD card.
Step 3: Recording Your Voice
Audacity is a great program for recording audio. You can download Audacity here. When using Audacity, be sure to set the track properties to 16-bit PCM, 16khz rate. Mono is fine, stereo will work, but I only hooked up a single speaker (and why does your clock need to be in stereo?).
Each number gets it's own wav. file. You'll need the following samples:
- geve.wav (good evening)
- morn.wav (good morning)
- anoon.wav (good afternoon)
- and.wav (and)
- oclock.wav (O'Clock)
- secs.wav (seconds)
- exact.wav (exactly)
- beep.wav, a beep sound
- standard.wav (Pacific standard time will be)
- dlight.wav (Pacific daylight time will be)
Also, if you have a laptop, you'll get better results using an external microphone. Depending on your laptop, you might get some hiss or buzz.
Step 4: Make it: Schematic
Step 5: Make it: Power and Propeller
Then add the Prop, connecting Vdd and Vss on both sides of the chip. Notice I've added 2 .1uF Ceramic caps to each power rail.
Now add the EEPROM and 2 10k resistors, right above the Prop
Finally, add pin headers and wires to connect the headers to RST and P30 and P31.
Step 6: Make it: Testing
Step 7: Make it: RTC
Add the DS1307, connecting it to P29 and P28, the same pins as the eeprom. Also add the watch crystal to the DS1307's P1 and P2.
Optionally, you can give the DS1307 a battery backup by either connecting a 3v battery to P3, or using a super cap and diode. The super cap will charge up whenever the power is applied to the circuit, and the small diode will make sure it only discharges to the DS1307 (instead of powering the entire circuit)
Step 8: Make it: SD Card, Speaker, Display
Connect the LCD Display. This is a complicated connection - refer to the schematic for each pin. Note that DB4-DB7 go through 4.7k resistors.
Finally add the switches you'll use for input.
Step 9: Make it: Programming
Step 10: Make it: Using the LCD UI and Propeller Platform SD
1 - The Propeller Platform SD is pre-assembled.
2 - Follow this instructable to put together the LCD UI.
3 - You don't need a Prop Plug. The Propeller Platform SD has a bootloader, so you just unzip this file and copy to the root of your SD Card.
4 - You'll need to add a headphone jack or just add hookup wire to a small speaker on the LCD UI. You can see in the photos how I did it.
That's it! Have fun with your new talking clock!