CB1¶

Product Profile¶

The BIGTREETECH CB1 is launched to provide a great solution to the insane shortage of Raspberry Pi CM4.
It outputs signals to the motherboard via the fast and convenient two 100 pins micro BTB connection header. Moreover, it is onboard 2.4G WiFi.

Features Highlights¶

CPU: ALLWINNER H616, Quad-core Cortex-A53 @1.5GHz
GPU: Mali G31 MP2, Support OpenGL3.2
RAM: 512MB/1GB DDR3L SDRAM
Display: Compatible with HDMI2.0A Interface, Support 4K Displays
Compatible with USB2.0 Interface
Support 100M Ethernet + 100M WiFi
Having the same BTB header as the Raspberry Pi CM4.

Specifications¶

Product Size	40mm x 55mm
Mounting Size	33mm x 48mm
Input Voltage	5V±5%/2A
Output Voltage	3.3V±2%/100mA
Output Voltage	1.8V±2%/100mA
WiFi	2.4G/802.11 b/g/n

Dimensions¶

Schematic¶

BIGTREETECH_CB1_V22_220812_SCH

Pinout¶

40 pin GPIO¶

The 40 pin GPIO on the motherboard when CB1 is used with motherboard like Manta M4P, M5P, M8P, PI4B_Adapter, etc.

Pin	Signal	Description	Pin	Signal	Description
1	3.3V		2	5V
3	NC		4	5V
5	NC		6	GND
7	PC7	GPIO71	8	PH0	GPIO224, UART0_TX
9	GND		10	PH1	GPIO225, UART0_RX
11	PC14	GPIO78	12	PC13	GPIO77
13	PC12	GPIO76	14	GND
15	PC10	GPIO74	16	PC11	GPIO75
17	3.3V		18	PC9	GPIO73
19	PH7	GPIO231, SPI1_MOSI	20	GND
21	PH8	GPIO232, SPI1_MISO	22	NC
23	PH6	GPIO230, SPI1_CLK	24	NC
25	GND		26	PG8	GPIO200
27	NC		28	PG7	GPIO199
29	NC		30	GND
31	PG6	GPIO198	32	PG9	GPIO201
33	NC		34	GND
35	PC6	GPIO70	36	NC
37	PC15	GPIO79	38	PH10	GPIO234, IR_RX
39	GND		40	PC8	GPIO72

**2 * 100 pins**¶

A Pin	Signal	Description	A Pin	Signal	Description
1	GND		2	GND
3	NC		4	EPHY-TXP	Ethernet TX Positive
5	NC		6	EPHY-TXN	Ethernet TX Negative
7	GND		8	GND
9	NC		10	EPHY-RXP	Ethernet RX Positive
11	NC		12	EPHY-RXN	Ethernet RX Negative
13	GND		14	GND
15	LINK_LED	Ethernet LED	16	NC
17	SPD_LED	Ethernet LED	18	NC
19	NC		20	NC
21	PH5	System LED(ACT)	22	GND
23	GND		24	PC15
25	PC8		26	PC6
27	PH10		28	NC
29	NC		30	PG6
31	PG9		32	GND
33	GND		34	NC
35	PG7		36	NC
37	PG8		38	PH6
39	NC		40	PH8
41	NC		42	GND
43	GND		44	PH7
45	PC9		46	PC10
47	PC11		48	PC12
49	PC13		50	PC14
51	SoC_RX	DEBUG UART	52	GND
53	GND		54	PC7
55	SoC_TX	DEBUG UART	56	NC
57	SDC0-CLK	MicroSD Card	58	NC
59	GND		60	GND
61	SDC0-D3	MicroSD Card	62	SDC0-CMD	MicroSD Card
63	SDC0-D0	MicroSD Card	64	PG11
65	GND		66	GND
67	SDC0-D1	MicroSD Card	68	PG12
69	SDC0-D2	MicroSD Card	70	PG13
71	GND		72	PG14
73	PG16		74	GND
75	NC		76	PI16	MicroSD Card detect
77	5V		78	NC
79	5V	In 2A	80	NC
81	5V	In 2A	82	NC
83	5V	In 2A	84	3.3V	Out 200mA
85	5V	In 2A	86	3.3V	Out 200mA
87	5V	In 2A	88	1.8V	Out 100mA
89	NC		90	1.8V	Out 100mA
91	NC		92	PWRON
93	FEL		94	NC
95	NC		96	NC
97	NC		98	GND
99	Recovery		100	Reset

B Pin	Signal	Description	B Pin	Signal	Description
101	NC		102	NC
103	USB1-DM	Host USB1	104	LineOut L
105	USB1-DP	Host USB1	106	LineOut R
107	GND		108	GND
109	NC		110	NC
111	TV_OUT	CVBS OUT	112	NC
113	GND		114	GND
115	NC		116	NC
117	NC		118	NC
119	GND		120	GND
121	NC		122	NC
123	NC		124	NC
125	GND		126	GND
127	NC		128	USB3-DM	Host USB3
129	NC		130	USB3-DP	Host USB3
131	GND		132	GND
133	NC		134	USB2-DM	Host USB2
135	NC		136	USB2-DP	Host USB3
137	GND		138	GND
139	NC		140	USB0-DM	OTG USB
141	NC		142	USB0-DP	OTG USB
143	NC		144	GND
145	NC		146	NC
147	NC		148	NC
149	NC		150	GND
151	HCEC	HDMI CEC	152	NC
153	HHPD	HDMI HotPlug	154	NC
155	GND		156	GND
157	NC		158	NC
159	NC		160	NC
161	GND		162	GND
163	NC		164	NC
165	NC		166	NC
167	GND		168	GND
169	NC		170	HTX2P	HDMI TX2 Positive
171	NC		172	HTX2N	HDMI TX2 Negative
173	GND		174	GND
175	NC		176	HTX1P	HDMI TX1 Positive
177	NC		178	HTX1N	HDMI TX1 Negative
179	GND		180	GND
181	NC		182	HTX0P	HDMI TX0 Positive
183	NC		184	HTX0N	HDMI TX0 Negative
185	GND		186	GND
187	NC		188	HTXCP	HDMI CLK Positive
189	NC		190	HTXCN	HDMI CLK Negative
191	GND		192	GND
193	NC		194	NC
195	NC		196	NC
197	GND		198	GND
199	HSDA	HDMI I2C	200	HSCL	HDMI I2C

Software Configuration¶

Network Settings¶

Ethernet¶

Plug-and-play with an Ethernet cable, no additional setup required.

WiFi Settings¶

After the OS writes to the SD card, there is a FAT32 partition named BOOT, open system.cfg file with Notpad, Notpad++ or VSCode.

Set WIFI_SSID as your actual wifi name and WIFI_PASSWD as your actual wifi password, The space character can be parsed normally without additional escape character. For example: WIFI_SSID="CB1 Tester"

Overlays Settings¶

After the OS writes to the SD card, there is a FAT32 partition named BOOT, open BoardEnv.txt file with Notpad, Notpad++ or VSCode.

Set as required as shown in the figure below.

The default value is console=display, This means that the UART0 of CB1 is used as the debugging port by default. We can use MobaXterm to connect to CB1 by UART0 and debug. If klipper wants to use UART0 to control the motherboard, we need to set it to console=serial, now klippe can use UART0 as /dev/ttyS0.

CB1 will automatically identify the HDMI resolution, but if your HDMI screen cannot report the resolution through the EDID normally, we can forcibly specify the resolution of CB1 output by uncomment extraargs=video and set the actual resolution.
For example:
BTT-HDMI7 resolution = 1024x600: extraargs=video=HDMI-A-1:1024x600-24@60
BTT-HDMI5 resolution = 800x480: extraargs=video=HDMI-A-1:800x480-24@60

Uncomment overlays=tft35_spi to enable TFT35 SPI screen.

Uncomment overlays=mcp2515 to enable MCP2515 spi to canbus module.

Uncomment overlays=tft35_spi mcp2515 If you want to use both TFT35 SPI screen and MCP2515 spi to canbus module

uncomment the following overlays and parameters to release 'spidev1.1' to user space, And 'spidev1.1' cannot be used together with TFT35_SPI and MCP2515.

 overlays=spi-spidev
 param_spidev_spi_bus=1
 param_spidev_spi_cs=1
 param_spidev_max_freq=1000000

NOTE: TFT35 SPI and MCP2515 multiplex a group of SPI1

SPI1_CLK=PH6
SPI1_MISO=PH8
SPI1_MOSI=PH7
TFT35_SPI_CS=PC7
MCP2515_CS=PC11
MCP2515_IRQ=PC9

SSH Connection¶

Install the ssh application Mobaxterm: https://mobaxterm.mobatek.net/download-home-edition.html

Insert the Micro SD card (installed OS) to motherboard, wait for system to load after power on, aprox. 1-2min. the ACT LED on the motherboard will flash continuously after startup successfully.

The device will automatically be assigned a IP address after successfully connected to the network

Find the device IP address in your router page

Or use the https://angryip.org/ tool，scan all IP address in the current network organize by names, find the IP named Hurakan, BTT-CB1 like shown below

Open Mobaxtermand click “Session”, and click “SSH”，inset the device IP into Remote host and click “OK” (note: your computer and the device needs to be in the same network)

Input the login name and password to enter the SSH terminal interface

login as: biqu
password: biqu

Software Installation¶

Download the OS Image

Please download and install the OS image we provided: https://github.com/bigtreetech/CB1/releases

Download and Install Writing Software

The official Raspberry Pi Imager: https://www.raspberrypi.com/software/

balenaEtcher: https://www.balena.io/etcher/

Both of the above software can be used, just choose one to download and install

Format SD card

Normally, you can format the SD card with the tools provided by the computer system. Completely format the SD card with professional SD card format software. https://www.sdcard.org/downloads/formatter/

Write OS
Raspberry Pi Imager

Insert a MicroSD into your computer.

Choose OS.

Select "Use custom", then select the image that you downloaded.

Select the MicroSD card and click "WRITE" (WRITE the image will format the MicroSD card. Be careful not to select the wrong storage device, otherwise the data will be formatted.)

Wait for the writing to finish.

balenaEtcher

Insert a MicroSD card to your computer through a card reader.

Select the image that you downloaded.

Select the MicroSD card and click "WRITE" (WRITE the image will format the MicroSD card. Be careful not to select the wrong storage device, otherwise the data will be formatted.)