RK3588 development board for high-end AI, server and digital-signage applications.
Octa-core (4 × Cortex-A76 + 4 × Cortex-A55) with a 6 TOPS NPU, LVDS / EDP /
V-by-One display outputs, HDMI 2.0a in and out, and USB 3.0 on a 150 × 81.2 mm
board.
This page is the hardware reference
Flashing, the firmware API and the guides
apply to every board. This page covers what is specific to the KTM-S88CD: its
connectors, pin assignments and electrical limits.
Connector map
RK3588 A76 + A55 150 × 81.2 mm DC12V RJ45 USB3.0 USB3.0 OTG HDMI out HDMI in Audio DC12V-in RS232 LVDS-BL I2C RS485 LVDS EDP V-by-one IR MIC USB1-3 SPK IR+LED GPIO
Swipe sideways to see the whole board. Tap a connector to jump to its pin definition. Positions are schematic, not to scale.
Specification
OS Android 13 CPU Rockchip RK3588 — quad-core Cortex-A76 + quad-core Cortex-A55NPU 6 TOPS, tri-core, INT4 / INT8 / INT16 / FP16 / BF16 / TF32 GPU ARM Mali-G610 MC4 — OpenGL ES 1.1/2.0/3.1/3.2 DDR LPDDR 8 GB (8 GB / 16 GB / 32 GB optional) Flash eMMC 32 GB (32 GB / 64 GB / 128 GB optional) Wi-Fi 802.11 a/b/g/n/ac, 2×2 MIMO, dual 2.4 / 5 GHz Ethernet RJ45 gigabit (1000 M) Screen interface LVDS, EDP, V-by-One HDMI HDMI 2.0a out (4K) and HDMI 2.0a in USB USB 3.0 RTC Yes — with scheduled power on/off Audio / Mic 3.5 mm earphone and microphone Camera Via USB
Power: DC 12 V / 3 A via 5.5 × 2.1 mm barrel (current depends on screen size).
The datasheet's "Other ports" summary (§3.18) lists 12 V / 2 A, but its electrical
specification gives a typical draw of 2.5 A (30 W, depending on screen size) —
already above 2 A. A 2 A adapter is the mistake to avoid: it shows
up as random reboots under load or a flash that drops mid-way. This page uses
12 V / 3 A throughout.
Internal expansion: LVDS, EDP, V-by-One (each with its own power and backlight
control header), 2 × RS232, RS485, 3 × USB, speaker, microphone, LED/IR, GPIO and
a touch-panel header.
Board dimensions
Size 150 mm × 81.2 mm Thickness 16 mm Top clearance 1.6 mm Bottom clearance 3.0 mm
Serial ports at a glance
The two RS232 headers and the RS485 header are driven through the standard serial
interface. The datasheet does not give a /dev/ttyS* node for them.
Port Device node Type RS232-1 — RS232, full duplex RS232-2 — RS232, full duplex RS485 — RS485, half duplex
The RS232/RS485 device nodes are not specified in the datasheet. Confirm on your
board with ls /dev/ttyS* or contact us. See the
firmware API overview for how the device API drives the board
(power scheduling, GPIO, display, network, kiosk lockdown).
Display ports
Pin Define Attribute Description 1 5V Power out 3.3V / 5V / 12V optional 2 12V Power out 3.3V / 5V / 12V optional 3 3.3V Power out 3.3V / 5V / 12V optional 4 GND GND Ground 5 GND GND Ground 6 GND GND Ground 7 D0N Output Pixel 0 negative data (odd) 8 D0P Output Pixel 0 positive data (odd) 9 D1N Output Pixel 1 negative data (odd) 10 D1P Output Pixel 1 positive data (odd) 11 D2N Output Pixel 2 negative data (odd) 12 D2P Output Pixel 2 positive data (odd) 13 GND GND Ground 14 GND GND Ground 15 CLK0N Output Negative sampling clock (odd) 16 CLK0P Output Positive sampling clock (odd) 17 D3N Output Pixel 3 negative data (odd) 18 D3P Output Pixel 3 positive data (odd) 19 D5N Output Pixel 0 negative data (even) 20 D5P Output Pixel 0 positive data (even) 21 D6N Output Pixel 1 negative data (even) 22 D6P Output Pixel 1 positive data (even) 23 D7N Output Pixel 2 negative data (even) 24 D7P Output Pixel 2 positive data (even) 25 GND GND Ground 26 GND GND Ground 27 CLK1N Output Negative sampling clock (even) 28 CLK1P Output Positive sampling clock (even) 29 D8N Output Pixel 3 negative data (even) 30 D8P Output Pixel 3 positive data (even)
3.4 EDP port — dual-contact 20-pin, 2.0 mm
Pin Define Attribute Description 1 VCC VCC — 2 VCC VCC — 3 GND GND Ground 4 GND GND Ground 5 EDP_TX0N Difference data Channel 0 6 EDP_TX0P Difference data Channel 0 7 EDP_TX1N Difference data Channel 1 8 EDP_TX1P Difference data Channel 1 9 EDP_TX2N Difference data Channel 2 10 EDP_TX2P Difference data Channel 2 11 EDP_TX3N Difference data Channel 3 12 EDP_TX3P Difference data Channel 3 13 GND GND Ground 14 GND GND Ground 15 XN Data clock Difference signal 16 XP Data clock Difference signal 17 GND GND Ground 18 GND GND Ground 19 GND GND Ground 20 NC NC NC
3.7 V-by-One port — 51-pin, 0.5 mm
Pin Define Attribute Description 1 GND GND Ground 2 VBX1-7P Difference data Channel 7 3 VBX1-7N Difference data Channel 7 4 GND GND Ground 5 VBX1-6P Difference data Channel 6 6 VBX1-6N Difference data Channel 6 7 GND GND Ground 8 VBX1-5P Difference data Channel 5 9 VBX1-5N Difference data Channel 5 10 GND GND Ground 11 VBX1-4P Difference data Channel 4 12 VBX1-4N Difference data Channel 4 13 GND GND Ground 14 VBX1-3P Difference data Channel 3 15 VBX1-3N Difference data Channel 3 16 GND GND Ground 17 VBX1-2P Difference data Channel 2 18 VBX1-2N Difference data Channel 2 19 GND GND Ground 20 VBX1-1P Difference data Channel 1 21 VBX1-1N Difference data Channel 1 22 GND GND Ground 23 VBX1-0P Difference data Channel 0 24 VBX1-0N Difference data Channel 0 25 GND GND Ground 26 VB-LOCKN LOCKN Negative sampling clock 27 VB-HTPDN HTPDN HTPDN 28/29 NC NC NC 30 SEL_SECTIO SEL_SECTIO Data 31/32 NC NC NC 33 I2CM_C_SCL I2CM_C_SCL Data 34 I2CM_C_SDA I2CM_C_SDA Data 35 NC NC NC 36 BLON BLON BL- data 37 E-PWM_H E-PWM_H PWM- data 38–42 GND GND Ground 43 NC NC NC 44–51 V-by-One VCC VCC-12V VCC-12V
Backlight and display power
3.2 LVDS power port — 6-pin, 2.0 mm
Selects the LVDS panel supply voltage by jumper.
Pin Define Attribute Description 1 3.3V LVDS VCC 3.3V 2 VCC-LVDS LVDS VCC 3.3V 3 5V LVDS VCC 5V 4 VCC-LVDS LVDS VCC 5V 5 12V LVDS VCC 12V 6 VCC-LVDS LVDS VCC 12V
3.5 EDP power port — 6-pin, 2.0 mm
Pin Define Attribute Description 1 3.3V LVDS VCC 3.3V 2 VCC-LVDS LVDS VCC 3.3V 3 5V LVDS VCC 5V 4 VCC-LVDS LVDS VCC 5V 5 12V LVDS VCC 12V 6 VCC-LVDS LVDS VCC 12V
3.3 LVDS backlight control port — PH2.0-6P
Pin Define Attribute Description 1 VCC Power out 12V 2 VCC Power out 12V 3 BL-EN Output Backlight enable 4 BL-ADJ Output Backlight adjust 5 GND GND Ground 6 GND GND Ground
3.6 EDP backlight control port — PH2.0-6P
Pin Define Attribute Description 1 VCC Power out 12V 2 VCC Power out 12V 3 BL-EN Output Backlight enable 4 BL-ADJ Output Backlight adjust 5 GND GND Ground 6 GND GND Ground
3.8 V-by-One backlight control port — PH2.0-6P
Pin Define Attribute Description 1 VCC Power out 12V 2 VCC Power out 12V 3 BL-EN Output Backlight enable 4 BL-ADJ Output Backlight adjust 5 GND GND Ground 6 GND GND Ground
Power
3.9 External power port — PH2.54-4P
Pin Define Attribute Description 1 12V Power in 12V 2 12V Power in 12V 3 GND GND Ground 4 GND GND Ground
Serial ports
The RS232 and RS485 headers are driven through the standard serial interface. The
device API (ItempApiPub) does not handle UART I/O; it covers
power , display , GPIO ,
network and kiosk .
3.10 RS232 (×2) port — PH2.0-4P
Two RS232 headers share this pinout.
Pin Define Attribute Description 1 GND GND Ground 2 TX I/O UART0 TX 3 RX I/O UART0 RX 4 VCC Power out 3.3V
3.11 RS485 port — PH2.0-4P
Pin Define Attribute Description 1 GND GND Ground 2 RS485-A I/O UART0 A 3 RS485-B I/O UART0 B 4 VCC Power out 3.3V
USB ports
Three internal USB headers, identical pinout (PH2.0-4P).
3.13 USB (×3) port — PH2.0-4P
Pin Define Attribute Description 1 GND GND Ground 2 DP I/O USB D+ 3 DM I/O USB D− 4 VCC Power out 5V
Audio
3.12 MIC port — PH2.0-2P
Pin Define Attribute Description 1 MIC- Input Microphone negative 2 MIC+ Input Microphone positive
3.14 Speaker port — PH2.0-4P
Pin Define Attribute Description 1 LP Output Left positive 2 LN Output Left negative 3 RN Output Right negative 4 RP Output Right positive
LED, IR and control
3.15 LED / IR port — PH2.0-5P
Pin Define Attribute Description 1 LED_R LED red LED red 2 LED_G LED green LED green 3 VCC Power out 3.3V 4 GND GND Ground 5 IR IN Input IR input
GPIO
These are the pins the GPIO API drives. The SDK names match the
Define column below.
3.16 GPIO port — PH2.0-5P
Pin Define Attribute Description 1 GPIO4_D5 I/O GPIO4_D5 2 GPIO4_D3 I/O GPIO4_D3 3 GPIO4_D4 I/O GPIO4_D4 4 PWR KEY Power key Power key 5 GND GND Ground
See GPIO for reading and driving these lines from code.
Touch panel
3.17 I2S port — FPC 0.5 mm, 10-pin
The datasheet titles this connector "I2S", but its pins (RST, INT, SCL, SDA) are
a touch-panel I2C interface, not an I2S audio bus. Treat it as touch-panel I2C
and verify with us before wiring an I2S device to it.
Pin Define Attribute Description 1 GND GND Ground 2 GND GND Ground 3 RST Reset Reset 4 INT Interrupt Interrupt 5 GND GND Ground 6 SCL SCL I2C clock 7 SDA SDA I2C data 8 VCC VCC 3.3V 9 GND GND Ground 10 GND GND Ground
Other interfaces
3.18 Other ports
Interface Detail Power DC 5.5 × 2.1 mm barrel, 12 V / 3 A (datasheet §3.18 says 2 A — see the note under Specification) HDMI out HDMI 2.0a HDMI in HDMI 2.0a Ethernet RJ45, gigabit (1 G) USB 2 × USB 3.0 Audio / Mic 3.5 mm earphone and microphone OTG Micro USB
Electrical specification
Parameter Min Typical Max Notes Power supply voltage — 12V — Ripple voltage — — 85 mV Power supply current — 2.5 A — Depends on screen size Power consumption — 30 W — Depends on screen size
API reference
The device API (power scheduling, GPIO, display, network, kiosk lockdown) is
documented under ItempApi reference . The serial ports above
are driven through the standard Android serial interface.
Downloads
Schematic, mechanical drawing and firmware image are on the
KTM-S88CD support page .
