Intro: IOT123 - ATTINY85 SOFTWARE SERIAL JIG Assembly
I've been using ATTINY85's for low-power sensor mashups. Originally I thought there was no way to debug these chips using a console and used some pretty "out there" methods to peek whats happening run-time.
Then I came across SoftwareSerial. Its a library, you define your TX and RX pins (yes we aint got many) and you get console debugging via a TTL-232 adapter.
I created an adapter that marries the relevant pins between an ATTINY and a TTL-232 (VCC and GND) and breaks out TX and RX for your own mapping. A header rail for VCC and GND are also broken out. This article describes the assembly of the jig; this article gives instructions for using SoftwareSerial with ATTINY85 using the Arduino Console window.
As the ATTINY85 seats lower than the surrounding headers in the DIL IC Socket, it is recommended a tag of Mylar (durable) tape is added to the chip(s) to facilitate easy removal from the Jig.
Step 1: Materials and Tools
- Double sided protoboard (6 x 7 holes)
- 8 Pin DIL IC Socket (1)
- 4P Female header with long pins (2)
- 6P Female header with short pins (3)
- Cyanoacrylate glue (1)
- Hookup wire (7)
- Solder Iron (1)
- Solder (1)
Step 2: Jig Assembly
- On the designated top of the board attach the DIL IC Socket through BLUE1 - BLUE8, bend pins outward on bottom and solder.
- On the top, apply Cyanoacrylate adhesive to sides of DIL IC Socket and insert 4P long pin headers into GREEN1 - GREEN4 and GREEN5 - GREEN8. When dry solder pins on underside, ensuring a solder bridge to adjacent pins (BLUE dots).
On the top, apply Cyanoacrylate adhesive to other sides of DIL IC Socket, and insert 6P Headers into YELLOW/ORANGE holes and PINK holes. When dry solder pins on underside.
On the top, apply Cyanoacrylate adhesive to the last gap onto the 6P header glued in #3. Insert 6P Header into RED/exposed holes. When dry solder pins on underside.
On the bottom, bridge the pins from PINK1 to PINK6. Then connect that bridge with a black wire to RED1.
On the bottom, bridge the pins from ORANGE1 to ORANGE4. Then connect that bridge with a red wire to RED2 and to BLUE1.
On the bottom, connect a green wire from RED3 to YELLOW1.
On the bottom, connect a white wire from RED4 to YELLOW2.
Step 3: Adding the Label
- Print the attached label with the width at 68mm onto adhesive labels.
- Cover with clear tape/contact.
- Cut to outer dotted line.
- Remove wax film and wrap label as shown.
- Add trimmed tape to seam on corner.
Step 4: Next Steps
- Attach jumpers from your preferred ATTINY pins for TX and RX to to the breakouts YELLOW1 and YELLOW2.
- Follow instructions for using SoftwareSerial. As stated in the article this method covers debugging, not the initial upload of the software.
- Careful with how you use strings in println statements: they suck memory.
- Peek values whilst developing your code.