ALFA Network R36M-E4G is a dual-SIM, N300 Wi-Fi, compact size platform
based on MediaTek MT7620A WiSoC. This product is designed for operation
with 4G modem (can be bought in bundle with Quectel EC25, EG25 or EP06)
but supports also Wi-Fi modules (miniPCIe slot has USB and PCIe buses).
Specification:
- MT7620A (580 MHz)
- 64/128/256 MB of RAM (DDR2)
- 16/32+ MB of FLASH (SPI NOR)
- 2x 10/100 Mbps Ethernet, with passive PoE support (24 V)
- 2T2R 2.4 GHz (MT7620A), with ext. LNA (RFFM4227)
- 1x miniPCIe slot (with PCIe and USB 2.0 buses and optional 5 V)
- 2x SIM slot (mini, micro) with detect and switch driven by GPIO
- 2x u.fl antenna connectors (for Wi-Fi)
- 8x LED (7 driven by GPIO)
- 2x button (reset, wifi)
- 2x UART (4-pin/2.54 mm pitch, 10-pin/1.27 mm pitch) headers on PCB
- 1x I2C (4-pin, 1.27 mm pitch) header on PCB
- 1x LED (8-pin, 1.27 mm pitch) header on PCB
- 1x DC jack with lock (12 V)
Other:
- there is a dedicated, 4-pin connector for optional RTC module (Holtek
HT138x) with 'enable' input, not available at the time of preparing
support for this board
- miniPCIe slot supports additional 5 V supply on pins 47 and 49 but a
jumper resistor (R174) is not installed by default
- U-Boot selects default SIM slot, based on value of 'default_sim' env
variable: '1' or unset -> SIM1 (mini), '2' -> SIM2 (micro). This will
work only if both slots are occupied, otherwise U-Boot will always
select slot with SIM card inside (user can override it later, in
user-space)
- U-Boot resets the modem, using PERSTn signal, before starting kernel
- this board supports 'dual image' feature (controlled by 'dual_image'
U-Boot environment variable)
Flash instruction:
You can use the 'sysupgrade' image directly in vendor firmware which is
based on OpenWrt (make sure to not preserve settings - use 'sysupgrade
-n -F ...' command). Alternatively, use web recovery mode in U-Boot:
1. Power the device with reset button pressed, the modem LED will start
blinking slowly and after ~3 seconds, when it starts blinking faster,
you can release the button.
2. Setup static IP 192.168.1.2/24 on your PC.
3. Go to 192.168.1.1 in browser and upload 'sysupgrade' image.
Signed-off-by: Piotr Dymacz <pepe2k@gmail.com>
New U-Boot version for MediaTek MT76x8/MT762x based ALFA Network boards
includes support for a 'dual image' feature. Users can enable it using
U-Boot environment variable 'dual_image' ('1' -> enabled).
When 'dual image' feature is enabled, U-Boot will modify DTB and divide
the original 'firmware' flash area into two, equal in size and aligned
to 64 KB partitions: 'firmware' and 'backup'. U-Boot will also adjust
size of 'firmware' area to match installed flash chip size.
U-Boot will load kernel from active partition which is marked with env
variable 'bootactive' ('1' -> first partition, '2' -> second partition)
and rename both partitions accordingly ('firmware' <-> 'backup').
There are 3 additional env variables used to control 'dual image' mode:
- bootlimit - maximum number of unsuccessful boot tries (default: '3')
- bootcount - current number of boot tries
- bootchanged - flag which informs that active partition was changed; if
it is set and 'bootcount' reaches 'bootlimit' value,
U-Boot will start web-based recovery which then updates
both partitions with provided image
Signed-off-by: Piotr Dymacz <pepe2k@gmail.com>
