The heart of the revolution
The base module of Revolution Pi called RevPi Core is equipped with
Raspberry Pi Compute Module. The compute module basically consists of
two ICs: a Broadcom BCM2835 SoC with 500 Mbyte RAM and a 4 Gbyte eMMC
Flash memory. The module is supplied with 1.8 V, 3.3 V and 5 V via the
mainboard socket. All IO signals are passed to the mainboard using this
single 200 pin wide socket.
RASBIAN (a Debian variant), using version Wheezy and an RT patch of kernel 4.1.13 is pre-installed.
Review the RevPi Data Sheet and Product Brochure here.
The power supply circuit is one of the most important parts
of the RevPi Core. In order to get as small heat from power dissipation as
possible we are using state-of- the-art high-efficiency DC-DC-converter
(efficiency over all is greater than 80%). These converters use 24 VDC input
(which is the usual case in industrial applications) to produce all supply
voltages needed for the Core.
But our Core module does not only run on the standardized
supply range of 20.4 V to 28.8 V but also runs on as little as 10.7 V input
voltage*. That means you can even use car batteries or solar panels as power
supply. At 24 V input any power loss of up to 10 ms will not influence
operation of RevPi Core (drawing full current from both USB ports) and even up
to 25 ms without USB load. Input voltage and functional earth is connected to
RevPi Core using heavy duty connectors at the bottom side.
A sophisticated protection circuit guarantees continuous
operation even under massive electrical or electro-magnetic interference on the
input power lines (provided that functional earth is connected properly).
Lightning strikes and nearby welding machines have been simulated in our test
laboratories but could not impress our RevPi Core modules.
* RevPi Core can only drive 2 x 500 mA USB 5 V supply using
input voltages greater than 11 V. EN61131 demands a minimum of 10 ms tolerance
against power failure which can only be guaranteed with input voltages form
20.4 V to 28.8 V. At 12 V input voltage this time decreases drastically,
especially when driving loads by USB ports.
Like Raspberry Pi, RevPi Core is equipped with common
- Connect RevPi Core to a LAN by using the RJ45 Ethernet
- The RevPi Core is equipped with two USB-A connectors at the
front side which can be used for USB 2.0 client devices. Both connectors can
drive up to 500 mA at their 5 V supply pins. Therefore you may plug USB drives
or surf sticks directly into these connectors without the need for an active
- You can connect an USB Host system (usually a PC) with the
RevPi Core using the Micro-USB connector in the middle of the front plate. The
RevPi Core will then boot in passive eMMC access mode and behave like an USB
client memory stick. That way you may flash the module for the first time using
an image file from a PC.
- One Micro-HDMI plug, e.g. for connecting a video monitor.
The data highway connecting all RevPi modules is called
PiBridge. The modules are physically connected to each other, using a system
connector on the top side. Three signal types are exchanged via this connector:
4 pins of the PiBridge are used for automatic module
detection during start-up phase. After this phase RevPi Core exactly knows
which modules are connected and in which physical position they are.
- 4 pins of the PiBridge are used for rapid data exchange of
small data packages using RS485 signals. This channel is also used for module
configuration during start-up phase. After configuration this channel is used
for cyclically exchanging data between RevPi Core and all IO modules connected.
- 8 pins of the PiBridge are used for rapid data exchange of large
amount of data using Ethernet signals. Up to now this channel is only used by
our modular gateway modules which may collect up to 512 Byte data cyclically
from nearly all relevant field buses.
One of our major
goals was to make Raspberry Pi ready for tough industrial environments, so it
could become a real IPC which meets the EN61131-2 standard.
* Not having heavy
USB loads and providing a free heat emission of the housing we have operated
RevPi Core up to 65 °C at 24 V input supply voltage without any problems. We
can’t guarantee cold start of a cooled down system at ambient temperatures less
than -30 °C using 24 V power supply voltage.
- Power supply: min. 10.7 V, max. 28.8 V,
max. 10 W
- Operating temperature: -40 to 55 °C*
- ESD protection: 4 kV / 8 kV according to
EN61131-2 and IEC 61000-6-2
- Surge / Burst tests: applied according
to EN61131-2 and IEC 61000-6-2 using power supply inputs , Ethernet line
and IO lines
- EMI tests: according to EN61131-2 and