WY7688

Suppor 3.3V or 5V power supply

Reference Schematic

WY Board

Specification

01
02
03
04
05

Pin Definition

调试串口 = debug serial port, 编程电压 =programe voltage, 时钟输出 = clock output
Pin Function 1 Function 2 Function 3 Function 4
1 UART_TXD0 GPIO # 12
2 3.3V 3.3V power supply
3 UART_RXD0 GPIO # 13
4 I2S_WS I2C_SCLK GPIO # 2 PCMCLK
5 I2S_SDO I2C_SD GPIO # 1 PCMDTX
6 I2S_CLK I2C_SD GPIO # 3 PCMFS
7 GPIO0 GPIO # 11 REF_CLKO PERST_N
8 I2S_SDI I2C_SCLK GPIO # 0 PCMDRX
9 I2C_SD GPIO # 5
10 I2C_SCLK GPIO # 4
11 SPI_CS1 GPIO # 6 REF_CLKO
12 SPI_CLK GPO # 7
13 SPI_MISO GPIO # 9
14 SPI_CS0 GPIO # 10
15 SPI_MOSI GPIO # 8
16 MDI_RP_P0
17 MDI_RN_P0
18 MDI_TP_P0
19 MDI_TN_P0
20 MDI_TP_P1 SPIS_CS GPIO # 14 PWM_CH0
21 MDI_TN_P1 SPIS_CLK GPIO # 15 PWM_CH1
22 MDI_RP_P1 SPIS_MISO GPIO # 16 UART_TXD2
23 MDI_RN_P1 SPIS_MOSI GPIO # 17 UART_RXD2
24 VDD_FLASH Flash programming voltage
25 5.0V 5.0V power supply
26 GND power ground
27 UART_TXD1 GPIO # 45
28 PERST_N GPIO # 36
29 UART_RXD1 GPIO # 46
30 WDT_RST_N GPO # 37
31 REF_CLKO GPIO # 38
32 EPH_LED1_N GPIO # 33
33 WLED_N GPIO # 35
34 EPH_LED0_N GPIO # 34
35 SD_D0 MDI_RN_P3 GPIO # 25
36 SD_CLK MDI_RP_P4 GPIO # 26
37 SD_D1 MDI_RP_P3 GPIO # 24
38 SD_CD MDI_TN_P3 GPIO # 23
39 SD_WP MDI_TP_P3 GPIO # 22
40 SD_D3 MDI_TP_P4 GPIO # 29
41 SD_D2 MDI_TN_P4 GPIO # 27
42 SD_CMD MDI_RN_P4 GPIO # 28
43 PWM_CH1 MDI_RN_P2 GPIO # 19
44 PWM_CH0 MDI_RP_P2 GPIO # 18
45 USB_DP
46 UART_TXD2 MDI_TP_P2 GPIO # 20 PWM_CH2
47 USB_DM
48 UART_RXD2 MDI_TN_P2 GPIO # 21 PWM_CH3

Stack Installation

Hardware Design Guide (Development Board)

UART0 recommended for system debug only
main board should not draw over 100mA from pin 3.3V
SPI, IIS, UART1, UART2, PWM, USB, IIC can be added if need
More information please read schematic of test board PDF in documents

Connector connection
Status LED, PWR power, Link0, 1 for ethernet status (gpio 43, 42)
Boot Mode select, I2S_SDI -> high to Boot, -> low to system reset mode
if flash is not enough to use, TF can be used as system disk, and flash only use for booting.
CH340G USB-TTL
Power supply
Ethernet connection

Play wav from TF card comman aplay -f cd -M ctl.wav
IO test, press WPS button for more than two seconds, this will be detect by Uboot and run GPIO test demo code.
Middle net port is WLAN, side is ethernet

Pin Confliction

If use SD card, ethernet 3 and 4 can not be used.
If use PWM, ethernet 2 can not be used.

Software

Support MTK official linux 2.6.36SDK,OpenWrt 3.10SDK，eCos SDK
Support OpenWrt official latest OpenWrt
U-boot - system lead, like windows bios
openwrt - system
art - wifi tune-up file

File download

Type	Original Link	Local Download	Note
Firmware - PandoraBox	MT7628AN_EVB	File:PandoraBox-ralink-mt7628-mt7628an-evb-squashfs-sysupgrade-115200.zip root / admin, 115200 192.168.1.1, DHCP: 192.168.1.2-192.168.1.254
Firmware - WY Testing Firmware	-	File:Wy-openwrt-mt7688an.zip	Support to test all on testing board resources.
Firmware - WY OpenWrt Firmware		SDK file (google drive link), 5PortEPHY.bin + dl.bin	Based on linux 3.18.45 core
UBoot + source (RaLink UBoot 4.3 version)	-	.bin+source	UBoot
Uboot/sdk tool - cross-complier	-	cross-compiler
MTK Official SDK	MediaTek_ApSoC_SDK?	SDK file (google drive link), File:MTK APSoC SDK User Manual.pdf
MTK Official OpenWrt	?	SDK file (google drive link), File:MTK-OpenWrt-3.10.14-SDK-Release-Notes.docx.zip
Script - AP-Client	-	File:Ap-client script.zip

Uboot Option

Enter when in 2-5 into update mode, enter when more than 7 seconds into GPIO test mode
Update mode also support serial port, or FTP mode

System backup

Update or backup via SPI Flash programmer see on this page Memory
Update U-Boot.bin file via programmer directly (address 00000000)

Update firmware via HTTP

Connect net cable to WLAN, power cable, serial debugging cable
Press WPS button between 2-5 seconds, serial debugging output info will show the board enter into update mode
Set your PC which is connected via net cable to board, IP address next to board, for example, if board is 10.10.10.2, then PC should be 10.10.10.3
Open 10.10.10.2 in browser and upload firmware, for example openwrt

Update firmware via TFTP

Set PCB ethernet IP address 10.10.10.3, use tool(3cdaemon) to setup PC as FTP server, put files in D:\bin\
Set U-boot to FTP upload mode, enter IP device/server address 10.10.10.3/10.10.10.2, and then enter file name

Compile U-Boot

request cross-compiler
copy compiler to /opt folder, tar xjvf
copy and use U-boot file, check makefile, it needs complier in opt folder
prepare to make -> make menuconfig, all configuration can keep default
make (if get java error, install default-jre)
finally will get uboot.bin file.
If any failure on updating U-boot, need to use SPI-flash programmer

Compile Source Openwrt

unzip openwrt, and unzip dl into openwrt folder
basic, use make menuconfig, in configuration choose:

Category	Setup	function
main	target -> Ralink RT288x/RT3xxx	chipset
main	subtarget -> MT7688 based boards	chipset
main	target profile -> Linkit7688	chipset
network	network->SSH->openssh-server	SSH
network	network->SSH->openssh-sftp-server	SFTP
network	network->Ser2net	Serial2, set /etc/ser2net.conf, to listen on port 8002 and output on serial2 you can set like this: 8002:raw:0:/dev/ttyS0:115200
UVC	see USB	page
sound card WM8960	Kernel modules -> sound support -> kmod-sound-core + kmod-sound-mtk + *kmod-sound-soc-core
sound card WM8960	sound -> *madplay-alsa
sound card WM8960	Utilities -> *alsa-utils
I2C support	Kernel modules -> I2S support -> kmod-i2c-core + kmod-i2c-ralink	Note to check if I2C turn on: i2c@900 { status = "okay"; };

Compile other files into firmware: Make new folder in openwrt firmware folder -> mkdir files -> put files into files folder
make V=99
bin file in /bin/ramips/..

Command control GPIO

Dev. board link0 link1 (ephy) corresponding to GPIO43 and42
run command mt7688_pinmux get, information shows:

..
Groups ephy - [ephy] gpio
..

now run command to set ephy to gpio - > mt7688_pinmux set ephy gpio
export GPIO43, first

cd /sys/class/gpio
echo 43 > export
cd gpio43

now directoy will be /sys/devices/10000000.palmbus/100006000.gpio/gpio/gpio43/
ls will find

active_low device direction edge subsystem uevent value

now to check gpio direciton -> cat direction, output in
echo out, and check again, output out
echo 1 >, or echo 0 >, value will be set

Other functions/modules

To use USB camera, see on this page USB

Following I2S for WM8960 sound card

Turn on I2S, change to

i2s {
    ralink,group = "i2s";
    ralink,function = "i2s";   // change gpio to i2s
};

add ref_clk to provide clock for WM8960, in make file: build_dir/target-mipsel_24kec+dsp_uClibc-0.9.33.2/linux-ramips_mt7688/linux-3.18.45/sound/soc/mtk/Makefile

KBUILD_CFLAGS += -DCONFIG_SND_MT76XX_SOC
KBUILD_CFLAGS += -DCONFIG_I2S_WM8960
KBUILD_CFLAGS += -DCONFIG_I2S_IN_MCLK
#KBUILD_CFLAGS += -DCONFIG_I2S_MCLK_12P288MHZ
KBUILD_CFLAGS += -DCONFIG_I2S_MCLK_12MHZ
KBUILD_CFLAGS += -DCONFIG_GDMA_EVERYBODY
KBUILD_CFLAGS += -DSURFBOARDINT_DMA=15

Test with following command to play

madplay  xxx.mp3
aplay  xxx.wav

Serial Port Usage

Use mt7688 serial programming, for the serial port 1,2 need to turn off the soft flow control, the default is open, close the reference picture;
Serial 2 can not use the problem: in the kernel directory arch / mips / ralink / mt7620.c inside the prom_soc_init function which add the following code:

u32 cfg; cfg = __raw_readl (sysc + 0x3c); cfg | = 0x0f; cfg | = 0x10; cfg | = 0x0f << 17; __raw_writel (cfg, sysc + 0x3c); Note: modify only use the network port 0, for the network port 1-4 can not be used.

Navigation menu

WY7688

Contents

WY7688

Reference Schematic

Specification

Pin Definition

Stack Installation

Hardware Design Guide (Development Board)

Pin Confliction

Software

File download

Uboot Option

System backup

Update firmware via HTTP

Update firmware via TFTP

Compile U-Boot

Compile Source Openwrt

Command control GPIO

Other functions/modules

Serial Port Usage