ST SPC582B-DIS, User Manual

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Hardware overview UM2174
12/23 UM2174 Rev 3
The jumpers SB1, SB2 and SB3 allow enabling further input clock as described in
Table 3
.
2.5 Reset circuit
Figure 11
shows the reset circuit; it generates a sharp signal to reset the microcontroller
when the pushbutton SW1 is pushed.
SW1 triggers the STM6315RB-2.63V and it generates reset pulse (active low signal); D2 is
turned on when the reset pulse is generated. The solder jumper SB16 allows to disconnect
PORST and NRST signals (in the default configuration it is closed).
The internal reset generator can be disabled and the reset signal can be provided by an
external source connected to CN6 pin3; to implement this configuration SB15 should be
removed.
Figure 11. Reset circuit
2.6 User LEDs, User Button
In the SPC582B-DIS board three LEDs are available for user purposes; see
Figure 12
. The
jumpers SB18, SB19 and SB20 allow disconnecting the anode of each LED and then let the
user to reserve these pins for a different purpose.
Table 3. Crystal oscillator - jumper configuration
SB1 SB2 SB3
Crystal (40MHz) Open Close Open
Ext Clock Close Open Open
Table 4. Reset circuit - jumpers configuration
SB15 SB16
Internal reset circuit Close Close
External reset circuit Open Close