Tenrec

Tenrec is a Raspberry Pi 4B

photo credit

2020-May-09 arrived from Newark

I set it up as a build machine, with its faster processor and more RAM and SSD on USB3 it runs circles around violet (Pi 3B+) and of course my little Pi Zeroes.

Hardware

Cable management is always an issue with the Pi, they stick out everywhere! :-)

• 4GB 4B
• Seeed heatsink kit so cute, had to have one. Probably superfluous.
• 7" Pi touch screen from Element14
• Multicomp Pro case, clear
• Corsair GTX 240GB SSD
• Startech USB3S2SAT3CB USB3.0-SATA3 cable w/UASP (lsusb id is 174c:55aa with ASMedia ASM1053E chipset)

I drilled a couple holes in the bottom of the case, attached RAM mount hardware.

I am borrowing the USB3 hub that lives in the back of my monitor and using it to power an Apple keyboard and a Startech USB3 SATA cable.

The combination of USB3, SATA3, and a reasonably fast SSD is working well.

Quirks tests

set quirks=174c:55AA in /boot/cmdline.txt then run sudo ./Storage.sh and observe the results

     Category                  Test                      Result
HDParm                    Disk Read                 162.96 MB/s
HDParm                    Cached Disk Read          161.84 MB/s
DD                        Disk Write                163 MB/s
FIO                       4k random read             IOPS ( KB/s)
FIO                       4k random write            IOPS ( KB/s)
IOZone                    4k read                   15504 KB/s
IOZone                    4k write                  23439 KB/s
IOZone                    4k random read            15545 KB/s
IOZone                    4k random write           21437 KB/s

With quirks turned off, it's faster

     Category                  Test                      Result
HDParm                    Disk Read                 270.66 MB/s
HDParm                    Cached Disk Read          265.18 MB/s
DD                        Disk Write                166 MB/s
FIO                       4k random read             IOPS ( KB/s)
FIO                       4k random write            IOPS ( KB/s)
IOZone                    4k read                   16087 KB/s
IOZone                    4k write                  20849 KB/s
IOZone                    4k random read            16183 KB/s
IOZone                    4k random write           23324 KB/s

Screen and touch screen rotation

In this case, the 7" screen is upside down. You can fix this! https://raspberrypiprojects.com/raspberry-pi-rotate-touch-screen/ Also the image did not fill up the screen, perhaps it was defaulting to 640x480?

In /boot/config.txt,

lcd_rotate=2
framebuffer_width=800
framebuffer_height=480

On the login screen with these settings there is a white band on the right, one or two pixels wide but I don't care. It goes away after login.

Power

I had the lightning bolt low voltage warning almost continuously until I plugged in only a hub to the USB ports. I am using a 5V 4A switching supply and a USB-C cable. My power meter says it's pulling just over an amp at 5.1 volts.

Software

I installed Raspian Buster Lite on the 8GB SD card that I am using to boot. Then I copied the contents to the SSD and set it up to mount /dev/sda2 as root.

Adding X11

I installed the window environment on the SSD. Also it goes without saying, emacs.

sudo -s
dpkg --configure -a
apt update
apt full-upgrade
reboot
apt install emacs-nox
apt install xserver-xorg xinit
apt install raspberrypi-ui-mods
reboot

Now I have a lightdm login screen, so I log in.

Adding Squeezelite

http://www.winko-erades.nl/installing-squeezelite-player-on-a-raspberry-pi-running-jessie/

Adding Alexa

Sample code is in /home/pi/alexa/.

I did a clean build after switching from Violet (Debian Stretch) to Tenrec (Debian Buster). Finally I did the build on the console on Tenrec after trying a few times from remote SSH sessions that got interrupted by random life events like dinner and walks.