Raspberry Pi 400

It’s the Master Compact of 2020

The only thing missing is a ssd interface on the board still have to hang it off the usb

That’s not too bad with USB3 – when RISCOS can do that.

Thats great but it would have been a much better machine if it had a slot to pop in an SSD or MVME drive even if it was connected via USB hub

Add a 40 pin ribbon cable if you want to add a HAT
HAT??? We need a new acronym for Hardware dangling on the end of a 40 Pin GPIO Male to Female Ribbon Cable – 150mm

I still remember, not necessarily fondly, the old “Dongle Dangler”, a 25pin parallel to parallel connector with ribbon cable for attaching protection devices.

I just tried booting RISC OS on a Rpi 400. It hangs at ‘InitSDIODriver’.

Unplugging SDIODriver gets past it. This message posted using a Rpi 400 running RISC OS.

Running stable at 2.2 GHz. Idle temperature is 34C according to CPUClock.

Graphics Resoloution: 1920x1080, 16M colours

Test                                                   Benchmark
Processor - Looped instructions (cache)                  5461791    3070%
Memory - Multiple register transfer                        80219   49517%
Rectangle Copy - Graphics acceleration test                 1295     535%
Icon Plotting - 16 colour sprite with mask                 50769    2538%
Draw Path - Stroke narrow line                             13489     864%
Draw Fill - Plot filled shape                              10202     699%
Draw Render - Render draw file                             15109    1667%
HD Read - Block load 8MB file                              30340    1017%
HD Write - Block save 8MB file                             29520     970%
FS Read - Byte stream file in                                502     242%
FS Write - Byte stream file out                              486     253%

HAT??? We need a new acronym for Hardware dangling on the end of a 40 Pin GPIO Male to Female Ribbon Cable – 150mm

Got it! – call it “Home” because…

…“wherever I lay my Hat that’s my home” (OK, I’ll get my coat, eventually)

Unplugging SDIODriver gets past it. This message posted using a RPi 400 running RISC OS.

Slightly less fixing than I expected. That a full RO Direct install?

I think that the Rpi 400 is based on the CM4 and the specific revision number (which identifies the Pi model number and revision) is used by the RISC OS HAL to determine the memory layout of the GPIO system and other things. As the CM4 came out after 5.28 was frozen, it has not yet been catered for. The Pi 400 came out after 5.28 had been released. In other words the list of revision numbers known to RISC OS, to decide where in memory certain things are, which are hardware dependent, does not yet include the Compute Module 4 or the Pi 400. SDIO, presumably, is one of the things affected. GPIO may not work either?

An update to HAL_BCM2835 will no doubt appear in due course.

The revision codes on the Pi Foundation site have not yet been fully updated to include CM4. The utility !ScreenHelp will display the revision code of a Pi.

It can be inferred that CM4 and Pi 400 have codes of the form (where the final number, 1, is the assumed revision number):

Pi 400:
A03131 1GB
B03131 2GB
C03131 4GB
D03131 8GB
CM4:
A03141 1GB
B03141 2GB
C03141 4GB
D03141 8GB

The revision code of the Pi 400 is C03130 according to the bootloader splash screen.

Looks like the thermal problems are completely solved. The highest temperature under load so far is about 40C.

Is it firmware changes that have solved it or a different physical layout of the Pi 400 board?

Hi Chris, I am just getting nothing at boot, just a black screen and flashing cursor, how do you bypass this? Thanks.

It’s the Master Compact of 2020

Wasn’t that a three box design (keyboard, boxy bit, monitor), with the bit at the back just holding floppies? Yeah… I’m sure it’s the same box they put the FileStore into.

Looks like the thermal problems are completely solved.

Have you watched any of the teardown videos on YouTube? The weight of the device is a bloody big metal heatsink.
[also, don’t take yours apart to peek inside, the big metal bit is thermally bonded to the processor]

We need a new acronym for Hardware dangling

AIM – for Accident In the Making.

just a black screen and flashing cursor, how do you bypass this

Try updating to the latest fixup4/dat and start4/elf.

https://github.com/raspberrypi/firmware/raw/master/boot/start4.elf
https://github.com/raspberrypi/firmware/raw/master/boot/fixup4.dat

Is it firmware changes that have solved it or a different physical layout of the Pi 400 board?

There’s a new CPU revision ‘C0’ and the heat sink is about the size of the keyboard.

Yeah, not working unfortunately even with those updated firmware files. :( nevermind.

Finally!!!!!! Hello from RISC OS on the Raspberry Pi 400.

Unplugging SDIODriver does allow RISC OS to start but with the slight disadvantage that the SD drive icon is not there. Long story short, I have two USB sticks on the case one FAT32 with the firmware and the other as SCSI with RISC OS, having failed to make a partioned USB drive. Boot from USB is enabled by default. (The rear USB sockets are too close together for the rather portly pens I have.)

Yeah, not working unfortunately even with those updated firmware files. :( nevermind.

Also make sure you are booting from USB.

Just writing to a USB drive now, thanks for the tips.

We initially tried 5.28 and had the same problem as Jay, updating just the firmware didn’t fix it but adding the latest 5.29 ROM did. So it seems you need 5.29 (latest?) and latest firmware inc. start4.elf and fixup4.dat

So it seems you need 5.29 (latest?) and latest firmware inc. start4.elf and fixup4.dat

OS5.28 is working here with this firmware.

bootcode.bin  15Oct20
fixup.dat     29Oct20
fixup4.dat    29Oct20
start.elf     29Oct20
start4.elf    29Oct20

Booting from a Fat32FS USB pen, and with SDIODriver unplugged.

Newbie question, how do you unplug SDIODriver?