Nokia N900

Nokia N900
Manufacturer	Nokia
Codename	Rover, RX-51
Dimensions	110.9mm x 59.8mm x 18mm
Release Date	2009-11-11
Category	Supported
Specifications
SoC	TI OMAP 3430 @600MHz
DRAM	256 MB Mobile DDR
Hardware Features
LCD	800x480 3.5" Resistive TFT
Video	PowerVR SGX530
Network	WL1251
Storage	32GB
USB (Host/OTG)	Micro USB 2.0 Slave
Software Features
Kernel	5.1
Serial	Yes,special hardware
Charging	Yes
USB Slave	Gadgets only
USB Host	With hacks
Touchscreen	Yes
Keyboard	Yes
Screen	Yes
TV-out	Yes
3D acceleration	Yes, closed driver
Vibration motor	Yes
Audio	Yes (complex, no ucm, no speaker protection)
Phone calls	WIP
SMS	Yes, no UI
Wifi	Yes, firmware required

Status

Feature	Leste supported	Notes
Kernel version	5.1	Mainline + PowerVR Patches: https://github.com/maemo-leste/n9xx-linux
Serial	Yes	Requires special hardware
Charging	Yes
Wireless	Yes	Firmware is non-free
Ethernet	N/A
Micro USB	Yes	USB Network, Mass Storage. OTG not working, although it might be possible
Keyboard	Yes
Screen	Yes
3D Acceleration	Yes	closed driver
Touchscreen	Yes	Resistive
Audio	Yes	Works (minus speaker protection), but requires complex alsa configuration and currently no ucm support
2G/3G data	Yes	Works with ofono - UI is WIP, see https://github.com/maemo-leste/connui-cellular/
4G data	N/A	no hardware
SMS	Yes	Works with ofono. Needs Leste UI
Phone calls	WIP	Works, no UI, poor quality for upstream audio, might require pulseaudio audio filters
Bluetooth	No	Driver needs some work
FM Transmitter	Yes	Install v4l-utils, then enable chip and set frequency using: v4l2-ctl -d /dev/radio0 -c mute=0,tune_power_level=120 -f <freq>
FM Receiver	No
Accelerometer	Yes
Compass	N/A	No hardware
Gyro	N/A	No hardware
Proximity sensor	Yes	evdev interface not supported in mce
Ambient Light Sensor	Yes
Vibration Motor	Yes
HDMI-out	N/A	No hardware
TV-out	Yes	Enable in alsamixer (Jack Function in alsamixer to TV OUT), enable with xrandr --output TV --mode 800x480 --same-as LCD. Set PAL/NTSC with xrandr --output TV --set SignalProperties PAL, and scale with xrandr --output TV --set TVScale 90.
GPS	Yes	Works with gpsd but is not integrated yet, see GPS
Infrared	Yes	TX only (hardware limitation).
Camera	No	Needs complex v4l work, no leste integration
Idle power consumption	~300mW	Device does not enter RET or OFF mode

Installation

• Latest image: https://phoenix.maemo.org/job/leste-image-n900/lastSuccessfulBuild/artifact/arm-sdk/dist/
• Image archive: https://maedevu.maemo.org/images/n900/

dd the image to an sd card. If using a Windows machine, you can use Etcher NB: Etcher does not warn you before starting the flashing operation, so please be extra careful that you choose the correct device to flash to

Then boot from the sd card using either 0xFFFF/flasher-3.5 or u-boot/bootmenu: http://talk.maemo.org/showthread.php?t=81613

U-Boot setup

If you don't want to configure u-boot from Fremantle, or your Fremantle rootfs is broken), or you just want to install quickly

1. Download 0xFFFF and u-boot from https://maedevu.maemo.org/images/n900/tools/

2. Turn off Nokia N900, issue the following command on PC and connect Nokia N900 to the PC: sudo ./0xFFFF -m test/u-boot-2013.04-2.bin -l

3. Open the keyboard slider on the N900, and then issue following command on PC to test boot: ./0xFFFF -b

This should present u-boot from which you can select external SD card and boot to Maemo Leste. If you are presented with a menu, select the option to boot from External SD card. If you just get a command prompt, type run sdboot.

To flash u-boot permanently, you can issue the following command

(BE CAREFUL THOUGH. THIS WILL REPLACE THE EXISTING FREMANTLE KERNEL. ONLY DO THIS IF YOU DO NOT CARE ABOUT THE EXISTING MAEMO INSTALLATION OR YOU KNOW HOW TO RECOVER FROM THIS CONDITION):

sudo ./0xFFFF -m test/u-boot-2013.04-2.bin -f

Existing Fremantle

1. Install "U-Boot with kernel 2.6.28-omap1"

2. Install "Linux kernel for power user (boot image for U-Boot)". This is optional, but recommended.

3. Add Maemo Leste menu item (run as root):

cat > /etc/bootmenu.d/30-maemo-leste.item << "EOF" &&
ITEM_NAME="Maemo Leste"
ITEM_KERNEL="uImage"
ITEM_DEVICE="${EXT_CARD}p1"
ITEM_FSTYPE="ext2"
EOF
u-boot-update-bootmenu

4. Reboot the device

Increase filesystem size

As of 2018/11, the latest pre-alpha image results in a 1.2GB root filesystem with about 100MB to spare. This can be extended, provided that your SD card is big enough. Perform the following steps on a Linux machine with none of the SD card's partitions mounted:

• assumption: /dev/sda2 is Leste root partition
• e2fsck -f /dev/sda2
• use parted/gparted/cfdisk/... to enlarge /dev/sda2 to the desired size
• resize2fs -p /dev/sda2
• e2fsck -f /dev/sda2

The latest images have a script, /etc/expandcard.sh from https://github.com/maemo-leste/image-builder/blob/master/rootfs-overlay/common/etc/expandcard.sh

Serial

http://n900.elektranox.org/serial-adapter.html

http://wiki.maemo.org/N900_Hardware_Hacking#Debug_ports

Notes

• Speakers are enabled by default, but be careful of very high frequencies/levels - there are concerns regarding the possibility to blow them

Also see: https://elinux.org/N900

Power Management

Power usage right now is reported to be about 80mA, which is quite a lot. On a good battery this will last for about 15 hours. Power management on the N900 is being worked on: https://github.com/maemo-leste/bugtracker/issues/170

• https://wiki.maemo.org/N900_Hardware_Power_management
• https://wiki.maemo.org/N900_Hardware_Power_Consumption

Run:

modprobe ledtrig-default-on

And:

echo default-on > /sys/class/leds/debug::sleep/trigger

To enable the OMAP sleep debug LEDs (on the keyboard). Open keyboard, turn off the screen with the slider, and the LEDs will turn off if the phone ever reaches sleep modes.

Currently it does not yet reliably reach any sleep modes.

This script can be used to decode idle states when this patch is applied: https://github.com/maemo-leste/n9xx-linux/blob/maemo/beowulf/debian/patches/0001_deeper_idle.patch

$ cat idlest.py
"""
00001fff 48005020 (584be965) cm_idlest_per blocking bits: 0007e000
f7df3fb9 48004a20 (b32988a8) cm_idlest1_core blocking bits: 0020c046
0000000d 48004a28 (f7aa95e6) cm_idlest3_core
"""

# 31 to 0
cm_idlest1_core_bits = [
'RESERVED',
'ST_MMC3',
'ST_ICR',
'RESERVED',
'RESERVED',
'RESERVED',
'ST_MMC2',
'ST_MMC1',
'RESERVED',
'ST_HDQ',
'ST_MCSPI4',
'ST_MCSPI3',
'ST_MCSPI2',
'ST_MCSPI1',
'ST_I2C3',
'ST_I2C2',
'ST_I2C1',
'ST_UART2',
'ST_UART1',
'ST_GPT11',
'ST_GPT10',
'ST_MCBSP5',
'ST_MCBSP1',
'RESERVED',
'ST_MAILBOXES',
'ST_OMAPCTRL',
'ST_HSOTGUSB_IDLE',
'ST_HSOTGUSB_STDBY',
'RESERVED',
'ST_SDMA',
'ST_SDRC',
'RESERVED',
]

cm_idlest1_core_bits = list(reversed(cm_idlest1_core_bits))

#inp = '0020c046'
inp = '00208042' # after rmmod hci_nokia and hci_uart

v = int(inp, 16)

#print(v)
b= "{0:b}".format(v)
print((32-len(b))*'0' + b)

for i in range(0, 32):
    is_set = (v & (1 << i)) >> i
    if is_set:
        print(cm_idlest1_core_bits[i])

Battery calibration

Nokia N900 has bq27200 integrated circuit for monitoring battery state. The datasheet can be found here: http://www.ti.com/lit/ds/symlink/bq27200.pdf. If you are curious, check the section called "Gas Gauge Operation" for how the battery calibration is done in a low level.

Here are described the steps necessary to calibrate your battery. This should help if you see "Battery not calibrated" message in the status applet.

• Fully charge Nokia N900. Don't detach the charger immediately, give it some time after you see "Fully charged" message (10 minutes should be enough).
• Detach the charger and don't attach it again until the battery is fully depleted. Remember: if you attach the charger (or USB cable) at least once, you will need to start the calibration from the beginning (fully charge the device again).
• You may use the device as you normally do. You may power it off, power it on, reboot. All as usual. Just don't connect the device to a charger or a PC using the USB cable.
• When your Nokia N900 has battery depleted, it will alarm you with the "battery low" sound.
• Wait for about 20 seconds and attach the charger. If the device was powered off because of battery depletion, it's fine. The battery should have done the calibration cycle. Just attach the charger to the device, give it a minute and press power button to start booting.
• If you still see "Battery not calibrated" message, reboot the device.

After the first calibration cycle you will see that it has ~1700 mAh for the fully charged battery. This value is wrong. It's how the battery calibration works in low level: it can't change the fully charged value of the battery in steps that exceed 12.5%. What this means for us: it's needed to repeat the calibration cycle several times to get more accurate value. It may take about 3-7 calibration cycles to get the proper mAh value for fully charged battery. If you spend some time on this process, you will get really accurate battery gauge and you will always know how much charge is remaining.

Tip 1. If for any reason you want to reset the battery calibration value to see the message “Battery is not calibrated” again, you should remove the battery from the device for about 6 hours. Tip 2. If you replace the battery, you may want to do 1-2 calibration cycles described above to update the gauge for your new battery.

Accessing MTD

List devices:

cat /proc/mtd

Mount:

apt install mtd-utils
mkdir -vp /mnt/fremantle
ubiattach -p /dev/mtd5
mount -t ubifs ubi:rootfs /mnt/fremantle