4D Systems PICadillo-35T

4D Systems is well known for their intelligent screens featuring a GPU like Goldelox and Picaso. This new board combines a chipKIT-compatible board with a high-definition 480x320 screen.

Technically speaking, the MCU is a PIC32 PIC32MX795F512L, the same featured in the chipKIT Max32, with 512 KB of flash and 128 KB of RAM.

The board sports a chipKIT UNO32 form-factor with 42 available I/Os. The remaining pins are used to drive the screen.

So driving a screen and having all the GPIOs available at the same time is now possible!

Unfortunately, there are some hardware compatibility issues. For example, the clock and data for I²C have been switched.

Pin 18 corresponds to A4 or SCL on the PICadillo but to A4 or SDA on the chipKIT Uno32. Correlatively, pin 19 corresponds to A5 or SDA on the PICadillo but to A5 or SCL on the chipKIT Uno32.

As a consequence, shields using the I²C bus can't work with the PICadillo.

The PICadillo-35T also features resistive touch, an audio amplifier and a speaker, a microSD-card slot, a 5V-jack input and a 6-pin connector for programmer / debugger.

From left to right:

The microSD-card slot features a push-pull mechanism.
The USB port uses the deprecated Mini B format, and not the now standard Micro B.
The 6-pin connector is ready for the a programmer-debugger like the chipKIT PGM.
The 5V connector uses a highly-compact plug.

Libraries

The display requires specific libraries developed by Majenko Technologies. Those libraries provide all the routines to manage the screen, touch, SD-card, audio and clock.

They are installed in the standard libraries folder on the sketchbook.

The screen is extremely fast and provides a very crisp image thanks to the high-density pixels. With 480x320=153,600 pixels, The screen features twice as many pixels as similarly sized 3.5" screens with only 320x240=76,800 pixels.

Despite being managed directly with 10-bit analog inputs, touch is responsive and accurate enough.

Same diagonal, but twice the resolution

Software

The PICadillo-35T offers a variety of options of IDEs:

Processing-based Wiring-compatible Arduino-like MPIDE
Wiring-compatible UECIDE
Microchip MPLABX IDE to be used with the chipKIT PGM programmer debugger
and also embedXcode.

MPIDE or Multiple Platform IDE is compatible with the Wiring / Arduino 23 framework.

As Processing-based Wiring-derived, it is platform-agnostic and runs on either Windows, Mac OS X or Linux.

Uploading a sketch to the board is extremely slow and can take up to 3 minutes for a medium-sized project even at the 115200 bps configured speed.

UECIDE or Universal Embedded Computing IDE initiated by Matt Jenkins of Majenko Technologies is also Wiring / Arduino compatible but no longer relies on the Processing IDE.

UECIDE is highly modular and based on components for boards, tool-chains and utilities.

MPLABX is the official IDE from Microchip, based on NetBeans and available for Windows, Linux and Mac OS X. MPLABX has a free version. The C++ compiler, also free, needs to be downloaded and installed separately.

MPLABX relies on the chipKIT PGM programmer-debugger to upload an debug programs.

On Mac OS X, embedXcode, embedded computing on Xcode, also supports the PICadillo-35T board.

Conclusion

The PICadillo-35T from 4D Systems offers a unique combination of a powerful MCU with a high-definition screen.

The chipKIT Uno32 form-factor ensures pin compatibility to virtually all the chipKIT and Arduino shields.

As always, 4D Systems provides high quality documentation, including schematics and application notes.

At less than USD100, the PICadillo-35T provides an interesting option with 42 GPIOs and a high-resolution screen.

Pros

Nice board with screen combination
High definition screen
Many GPIOs available
Audio amplifier and speaker
Large choice of IDEs

Cons

Underlying framework still based on Wiring / Arduino 0023
Slow upload
Some hardware compatibility issues

Wrap-Up

Interesting MCU board with integrated screen
Fast and high definition screen
Arduino Uno and chipKIT Uno32 form-factor with
Many GPIOs available
Large choice of IDEs