Ublox IRIS-W10 Series, User Manual

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EVK-IRIS-W10 - User guide
UBX-23007837 - R03 Hardware description Page 16 of 43
C1-Public
3.2.1 Automatic bootloader / Bootstrap
Figure 16 shows bootloader configuration and sources available to user. Several signals and
DIP switch combinations used to configure the EVK so it can boot in several scenarios.
Figure 16: Bootloader schematic
EVK has two main methods to bootstrap IRIS-W10 module:
1. Default method - Using DIP switch SW3 with resistors R82, R94, R99 and R103
o
Four active-high signals ( EXT-FREQ , EXT-PRI , EXT-GNT , EXT-REQ ) are used to select
boot source. They correspond to CON3, CON2, CON1 and CON0 respectively in the
table shown in
Figure 16.
o
For example, to select ISP as boot source, GND the signal EXT-REQ on SW3.
Alternatively, other configurations are possible as described in the table data shown in
Figure 16.
2. Alternate method – Combination of button
SW7, R216, R218
,
R212, R213, R214,
and
R215 as shown in Table 2 .
BOOT button Installed resistor Boot source
SW7 R216 Serial
R218 ISP
R216, R218 SDIO
-
R212 USB
R212, R213 SDIO
R212, R215 SPI EEPROM
R214 Serial
R215 ISP
Table 2: Boot/strap-in configuration
☞
By holding EXT-REQ signal to GND,
blhost.exe
can be used to program firmware in ISP
mode. With this firmware, it is possible to perform full flash recovery if IRIS-W10 module
ended in a faulty state while flashing or running an application. See also the blhost user
guide [
11 ].