UUGear RasPiKey User manual

Copyright © 2021 UUGear s.r.o. All rights reserved.
RasPiKey
Plug &Play 16G/32G eMMC Module for Raspberry Pi
User Manual (revision 1.02)

Copyright © 2021 UUGear s.r.o. All rights reserved.
Table of Content
What is RasPiKey?.............................................................................. 1
What is in the Package? ...................................................................... 2
RasPiKeySpecifications...................................................................... 3
Before Booting with RasPiKey........................................................... 4
Update Bootloader (Optionalfor Raspberry Pi 4B only) .......................................................4
Enable SSH Login and Configure Wi-Fi Connection............................................................4
Using RasPiKey.................................................................................. 7
DDR52 Timing Mode......................................................................... 8
Benchmarks....................................................................................... 10
Acknowledgement............................................................................. 12
Revision History................................................................................ 13

1
What is RasPiKey?
RasPiKey is a 16GB/32GB eMMC module that can be inserted into Raspberry Pi’s micro SD card slot.
It works like a micro SD card with better read/write performance (especially for 4k read/write) and
have longer lifetime.
RasPiKey has Raspbian (Raspberry Pi OS) preinstalled and allows you configure SSH login and Wi-Fi
connection before booting your Raspberry Pi. As a result, you can use your Raspberry Pi without
display, keyboard and mouse, and access your Raspberry Pi via SSH session on your PC.
RasPiKey is a “plug and play” accessory to most Raspberry Pi models. If you have Raspberry Pi 4B
from rather old batch, which has rather old firmware that could not recognize RasPiKey, you may need
to update the bootloader of your Raspberry Pi 4B beforehand.
There are two varieties of RasPiKey: the 16GB RasPiKey comes with a black lanyard, while the 32GB
RasPiKey comes with a blue one.

2
What is in the Package?
Each RasPiKey package contains:
RasPiKeyboard x 1
lanyardx 1
* 32GB version has lanyard in blue color instead.

3
RasPiKeySpecifications
Dimension:
32mm x 19mm x 1.6mm
Weight
1g
eMMC
16GB: Samsung KLMAG1JETD-B041 (datasheet)
32GB: Samsung KLMBG2JETD-B041 (datasheet)
Working Voltage
3.3V
Benchmarks on Pi 3B
hdparm test: ~23 MB/sec
ddtest:~23 MB/s
4k read: ~11 MB/s
4k write: ~10 MB/s
Benchmarks on Pi 4B
hdparm test: ~45 MB/sec
ddtest:~34 MB/s
4k read: ~15 MB/s
4k write: ~15 MB/s
Operating Temperature
-30℃~80℃(-22F~176F)
Storage Temperature
-40℃~85℃(-40F~185F)
Humidity
0~80%RH, no condensing

4
Before Booting with RasPiKey
If you are not using Raspberry Pi 4B, and you have display, keyboard and monitor connected to your
Raspberry Pi, you can just insert RasPiKey into the micro SD card slot and directly use it like a normal
SD card. RasPiKey already have OS pre-installed, so it can directly boot your Pi.
Update Bootloader (Optionalfor Raspberry Pi 4B only)
If you are using Raspberry Pi 4B, you may (or may not) need to update the bootloader to have
RasPiKey supported.It depends on the Raspberry Pi 4 you have: earlier batch of Raspberry Pi 4 may
have rather old bootloader, which could not recognize RasPiKey. If your Raspberry Pi 4 is recently
purchased, then most probably you don't need to update its bootloader, and it can be directly boot with
RasPiKey.
You can run this command to verify the bootloader on your Pi 4:
If the printed release date of bootloader is later than September 3rd2020, then you don’t need to update
bootloader for your Pi 4.
In case you need to update bootloader. You can find the official released bootloader here.
Here we offer a much simpler way to update the bootloader:
1. Download this update_bootloader.zip file, or you can find it in RasPiKey’s boot partition.
2. Extract its content to a micro SD card
3. Insert the micro SD card into Raspberry Pi and power on
4. Wait for one minute.
5. Power off and remove the micro SD card.
After going through these steps, you have updated the bootloader on your Raspberry Pi 4B, and now it
can work with RasPiKey.
Enable SSH Login and Configure Wi-Fi Connection
If you want to use your Raspberry Pi without connecting any monitor, keyboard or mouse, you can
enable SSH login and configure Wi-Fi connection before you boot your Raspberry Pi with RasPiKey.
You will need a computer with micro SD card reader. If your computer doesn’t come with micro SD
card reader, you can use a USB SD card reader.
vcgencmd bootloader_version

5
After inserting RasPiKey into micro SD card reader, its “boot” partition will be recognized as a USB
disk on your computer (usually named “boot”). There you can find these files:
RasPiKey.exe
RasPiKey_MAC
RasPiKey_ARM
RasPiKey_X86
RasPiKey.zip
Depending on the computer and operating system you are using, you will use one of them to finish the
configuration:
Computer and Operating System
Action
PC + Windows
Run RasPiKey.exe
iMac, Mac Pro or MacBook + Mac OS X
Run RasPiKey_MAC
Raspberry Pi + Raspbian
Run RasPiKey_ARM
PC + Linux
Run RasPiKey_X86
Other
Extract RasPiKey.zip and edit the files inside.
When you run an executable file, it will request you to input some parameters to configure Wi-Fi
connection:
If you don’t have Wi-Fi, or you prefer to use cable to connect Raspberry Pi to the network, you can
input some dummy data here. The programme will generate the “wpa_supplicant.conf” file and the
empty “ssh” file in the same directory. The “wpa_supplicant.conf” file contains the parameters to
configure Wi-Fi connection, while the empty “ssh” file will enable the SSH login for you.

6
If for any reason you cannot run the suitable executable file, you can extract the RasPiKey.zip file and
edit the “wpa_supplicant.conf” file. The “ssh” file doesn’t need to be edited because it is empty.
Remarks: the “wpa_supplicant.conf” and “ssh” files will be automatically removed after booting your
Raspberry Pi with RasPiKey, however the configuration has been made and you don’t have to do it
again (unless your Wi-Fi parameters get changed).

7
Using RasPiKey
You can use RasPiKey like a normal micro SD card with OS installed. You insert it into the micro SD
card slot on Raspberry Pi, and then power it on.
If your Raspberry Pi has display, keyboard and mouse connected, you have nothing to worry about and
immediately enjoy using your Pi with RasPiKey.
If your Pi doesn’t have display, keyboard or mouse, you may want to use it via SSH session, which
needs your Pi to be connected to your network. If you have configured the Wi-Fi connection
beforehand, you just need to wait until your Raspberry Pi finishes the boot and connect to your Wi-Fi.
Or you use a network cable to connect Raspberry Pi to your local network.
Given the empty “ssh” file is in RasPiKey’s boot partition, you can ensure SSH login will be enabled
on your Raspberry Pi.
During the first boot with RasPiKey, your Raspberry Pi will adjust the pattern size and reboot,
this will make it a little longer until you can SSH it.
You can use this command to login via SSH session:
Sometimes it may complain about not knowing the “raspberrypi” host. In the majority of cases this
problem will disappear after waiting for a while. If the problem persists, you can use this command to
list all machines in your network:
This command exists in Windows, Mac OS X and Linux, what a handy tool!
If you run this command before and after booting your Raspberry Pi, you can figure out which IP
address is for your Pi, by comparing the outputs of this command. Then you can login with:
ssh pi@<IP address of your Pi>
arp -a
ssh pi@raspberrypi

8
DDR52 Timing Mode
DDR mode for eMMC was introduced in MMC 4.4 standard. The DDR52 timing mode can support
frequency up to 52MHz and can almost double the performance of eMMC module (such as RasPiKey)
on Raspberry Pi.
In order to support DDR52 mode, your Raspberry Pi may need to have the firmware upgraded.
Although the patch for supporting DDR52 timing mode has been committed, at the time of writing this
chapter, the patch has not been replicated to the official repository yet, once it does, you can upgrade
the firmware with these commands:
After the upgrade and reboot your Raspberry Pi, you can run this command to confirm if the DDR52
mode has been supported:
It should print out something like this:
clock: 52000000 Hz
actual clock: 50000000 Hz
vdd: 21 (3.3 ~ 3.4 V)
bus mode: 2 (push-pull)
chip select: 0 (don't care)
power mode: 2 (on)
bus width: 2 (4 bits)
timing spec: 8 (mmc DDR52)
signal voltage: 0 (3.30 V)
driver type: 0 (driver type B)
The result above means the DDR52 timing mode has been supported, and your RasPiKey has much
better performance on Raspberry Pi 4.
sudo cat /sys/kernel/debug/mmc0/ios
sudo apt update, sudo apt full-upgrade

9
However, if you see something different, like this:
clock: 52000000 Hz
actual clock: 50000000 Hz
vdd: 21 (3.3 ~ 3.4 V)
bus mode: 2 (push-pull)
chip select: 0 (don't care)
power mode: 2 (on)
bus width: 2 (4 bits)
timing spec: 1 (mmc high-speed)
signal voltage: 0 (3.30 V)
driver type: 0 (driver type B)
It means you need to upgrade the firmware to support the DDR52 timing mode.
You can run this command to make the upgrade:
sudo apt full-upgrade

10
Benchmarks
We follow Jeff Geerling’s blog posts (thank you Jeff) to do the benchmarks for RasPiKey.
Jeff wrote this blog post about the benchmarks on Raspberry Pi 3B+. We do exactly the same
benchmarks with RasPiKey and append the result to the diagram from Jeff’s blog post:
Benchmarks on Raspberry Pi 3B+

11
Jeff also wrote another blog post about the benchmarks on Raspberry Pi 4B.Again we do exactly the
same benchmarks with RasPiKey and append the result to the diagram from Jeff’s blog post:
Benchmarks on Raspberry Pi 4B (with DDR52 timing mode supported by firmware)
Please notice the benchmarks above are obtained on Raspberry Pi 4B with firmware updated to support
DDR52 timing mode. Please read the DDR52 Timing Mode chapter for more details.

12
Acknowledgement
We would like to thank Tim Gover (Raspberry Pi Trading Ltd) and his teamon supporting RasPiKey
(and other eMMC modules) on Raspberry Pi 4B, and their works on supporting the new DDR52 timing
mode.
We would also like to thank Dr. Tomas Lindén, who promoted the supporting of DDR52 timing mode
on Raspberry Pi, reminded us about the firmware upgrade, and also provided us important information
to perform further tests.

13
Revision History
Revision
Date
Description
1.00
2019.10.26
Initial revision
1.01
2020.09.01
Add information about newly supported DDR52
timing mode and new benchmark for RasPiKey on
Raspberry Pi 4B.
1.02
2021.01.07
Add information about 32GB version.
Add benchmarks table for Raspberry Pi 4B
More information for updating bootloader