Installation Instructions

Table Of Contents
L508 Hardware Design
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Table 27 Forced download interface definitions
Pin No. Pin Name I / O type Functional description
85 DL_KEY DI
Connect DL_KEY to VDD1V8 before boot on,
then the system will enter USB forced download
mode
4.14.2 Forced USB download interface application
MODULE
DL_KEY
VDD1V8
1K
Figure 29 L508 download reference circuit
4.15 SD card interface
4.15.1 Pin Description
The module supports SD card with 4-bit data interface, or devices based on SDIO protocol. SD
interface level can be adjusted at 1.8/3.0V.
Table 28 SD card interface definitions
Pin No. Pin Name I / O type Functional description