Realtek Semiconductor RTL8773B - Keys and LEDS

RTL8773B Motherboard User Guide
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·Copyright 2019 Realtek Semiconductor Corporation.
All Rights Reserved.
2.2.3 Keys and LEDS
Before using Keys and LEDs on evaluation board, their control pins should be
connected to RTL8773B Motherboard IOs. Default pin assignment is provided by
directly shorting jumper on J3、J6、J44 and J45 as shown in Figure 2-4.
The default mapping table for LEDs and KEYs is shown as Table2-1. Control pins of
Keys and LEDs on J3、J6、J44 and J45 can be connected to different RTL8773B
Motherboard IOs. For example, Key0’s control pin on J6 is Pin2. By putting jumper
wire on J6.1 and J6.2, we can read key value through M1_1.
Figure 2-4 Keys and LEDs Control jumper
Table 2-1 Keys and LEDs Map
LEDS name
Pin
name
Keys
name
Keys
name
Pin
name
LEDS name
M1_1 KEY0 KEY1 M0_1 LED1
M1_2 KEY1 KEY2 M1_0 LED2
M1_4 KEY2 KEY3 M2_1 LED3
M1_5 KEY3 M1_3 LED4
M4_1 KEY4 M2_3 LED5
LED9 M3_0 KEY5 M2_4 LED6
LED10 M3_1 KEY6
LED11 M2_2 KEY7
Tips: One KEY and LED cannot be connected to two IOs at the same time.
In addition, as shown in Figure2-5, the Keys with pull-up resistors (KEY0, 2, 4, 6
marked by red arrows) are all active-low, while the Keys with pull-low resistors
(KEY1, 3, 5, 7 marked by blue arrows) are all active-high. Users can choose
either of two types according to the specific development requirements.