Customizable carrier boards showcase Raspberry Pi CM4
Oct 19, 2020 — by Eric Brown 7,846 viewsGumstix has launched six carriers featuring the Raspberry Pi CM4, some of which offer Google’s Edge TPU. A CM4 Dev Board is joined by boards for robotics, Pixhawk drones, PoE smart imaging, and conversion to CM3-based carriers.
Long-time embedded Linux vendor Gumstix, which is now owned by Altium, has jumped all over the new Raspberry Pi Compute Module 4 (CM4) with a sextet of carrier boards that can be customized by the Geppetto online development service. Two of the boards are equipped with Google’s Edge TPU AI accelerator.


Gumstix Raspberry Pi CM4 Development Board (left) and Gumstix Raspberry Pi CM4 Robo
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The six new Gumstix carriers for the RPi CM4 include the following, with more details farther below:
- Gumstix Raspberry Pi CM4 Development Board — $130 — full-featured carrier with GbE, HDMI, DSI, 2x CSI2, USB, and M.2
- Gumstix Raspberry Pi CM4 PoE Smart Camera — $95 — mates RPi cam connector with Edge TPU and GbE with 9W PoE PD
- Gumstix Raspberry Pi CM4 Robo — $30 — small robotics breakout board with micro-HDMI, DSI, 2x CSI2, USB type-C, and 2x RPi cam connectors
- Gumstix Raspberry Pi CM4+Pixhawk FMUv6 — $180 — Designed for Pixhawk MAV drones and rovers with Edge TPU, STM32F7 MCU, IMU, GPS, 2x RPi cam links, microSD, 2x USB Type-C, etc.
- Gumstix Raspberry Pi CM4 Uprev — $30 — converts RPi CM4 for use on CM3-ready boards
- Gumstix Raspberry Pi CM4 UprevAI — $75 — same as Uprev, but adds Edge TPU
The Linux-powered, $25 to $90 Raspberry Pi CM4 module has the same Broadcom BCM2711 SoC with 4x 1.5GHz Cortex-A72 cores that is used on the Raspberry Pi 4. The module ships with 2GB to 8GB LPDDR4-3200 RAM and 0GB to 32GB eMMC. There is a GbE controller with PoE support, optional 802.11ac with BT 5.0, and new support for dual 4K HDMI ports and PCIe 2.0. Other features include 2x and 4x MIPI-DSI and -CSI interfaces.


Raspberry Pi Compute Module 4 (left) and new IO Board
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The CM4 switches from the SODIMM connector of the RPi CM3+ and CM3 to dual (low speed and high speed) 100-pin, perpendicular Hirose DF40 connectors. This enables a smaller 55 x 40 x 4.7mm footprint compared to the earlier 67.6 x 31mm but prohibits backward compatibility to earlier carriers. There is also an updated, more fully featured IO Board carrier that can act as a sandwich-style SBC. (For a Gumstix analysis of the CM4, see this blog entry.)
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Google’s Edge TPU, which is available on the Smart Camera and Pixhawk boards, runs at 4 TOPS using 0.5 watts for each TOPS (2 TOPS per watt). The chip is designed to run TensorFlow Lite ML and AutoML Vision Edge models for high-speed ML inferencing. The Edge TPU is implemented here with the solderable Coral Accelerator Module, which just debuted on Google’s Coral Dev Board Mini SBC, a stripped down version of the original Coral Dev Board.
Geppetto manufacturing fees waived
All the Gumstix Raspberry Pi CM4 embedded boards were designed and built with the drag and drop Geppetto design tool, which allows browser-based modification of design templates. Geppetto lets users preview a 3D view and download free CADfiles (.brd) and schematic (.sh) files of saved designs. To support the CM4 launch, Gumstix is waiving the $1,999 manufacturing fee at checkout for CM4-based designs. Customers pay only the cost of board and quantity ordered plus tax and shipping.
For more details, check out our March report on a similar promotion provided by Gumstix for all Raspberry Pi based designs. The earlier promotion lasted six weeks but Gumstix gave no end date for the current waiver. Gumstix has previously launched Raspberry Pi CM3-based carriers such as its Chatterbox Alexa Voice Service.
Gumstix also offers carrier board families for other compute module platforms such as Nvidia’s Jetson Nano. Last month, Gumstix and Altium announced that Toradex has licensed Geppetto for customers using its Arm-based, Linux supported Verdin and Colibri modules.


Gumstix Raspberry Pi CM4 Development Board detail views
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Gumstix Raspberry Pi CM4 Development Board — The Raspberry Pi CM4 dev board amplifies the CM4 module with Gigabit Ethernet, USB 2.0 host, micro-USB device, and micro-USB serial console ports. This general-purpose carrier provides an HDMI port, a touch-enabled DSI interface, and 2x CSI2 base connectors for the Raspberry Pi Camera. Other specs include an M.2 M-key socket with SSD support and a 40-pin Raspberry Pi GPIO header. The board has as 12VDC input jack along with reset and user buttons.


Gumstix Raspberry Pi CM4 PoE Smart Camera
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Gumstix Raspberry Pi CM4 PoE Smart Camera — The PoE Smart Camera board combines the CM4 with a GbE port with 9W, 802.3af Power-over-Ethernet PD, which lets you power the board and attached camera over Ethernet. The tiny board offers a vertical Raspberry Pi Camera connector and a Coral Accelerator Module with the Edge TPU. Other features include an I2S-based mic.

Gumstix Raspberry Pi CM4 Robo detail view
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Gumstix Raspberry Pi CM4 Robo — Ready for deployment on robot rovers and other autonomous devices, the Robo board features dual Raspberry Pi Camera connectors that can provide either stereoscopic depth mapping for object avoidance or front- and back-facing cameras for feature identification or manual control. The board is equipped with USB 2.0 host and USB Type-C with power delivery, as well as a micro-HDMI port and a MIPI-DSI connector with touch support. UART and I2C JST connectors enable connections to a PWM motor controller board or control MCU. Other features include a piezo mic, reset button, dual addressable LEDs, and a user button.


Gumstix Raspberry Pi CM4+Pixhawk FMUv6, front and back
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Gumstix Raspberry Pi CM4+Pixhawk FMUv6 — This “coming soon” controller board conforms to the Pixhawk v6 standards for Flight Management Units. The board is designed for drones such as micro-aerial vehicles (MAVs), as well as rovers. Gumstix’s earlier AeroCore 2 board also targeted MAVs. The Pixhawk board is equipped with an ST Micro STM32F7 MCU, a Coral Accelerator Module with Edge TPU, and 256kb FRAM. The board provides dual RPi Camera connectors, a microSD slot, USB Type-C PD, micro-USB serial console, 8x octal PWM outputs, and an accelerometer, magnetometer, gyro, and barometer. There are also Pixhawk-compliant GPS, analog power, RC, and CAN connectors.

Gumstix Raspberry Pi CM4 UprevAI detail view
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Gumstix Raspberry Pi CM4 Uprev and UprevAI — The Uprev adapter boards allow the Raspberry Pi CM4 to be used on most existing CM3 boards. The CM4’s GPIOs, communications signals, and power pins are re-routed from the CM4’s dual Hirose connectors onto a CM3-style SODIMM edge connector to match the pin-out of the CM3. The UprevAI model adds the Coral Accelerator Module.
Further information
The Gumstix Raspberry Pi CM4 Development Board is shipping now for $130. The other Gumstix CM4 carriers are available for pre-order at the prices listed farther above. We saw no mention of ship dates for these other boards. More information and links to shopping pages may be found on the Gumstix CM4 launch page.
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