Hardware layout and configuration
UM1817
12/58
DocID026902 Rev 3
2.1.2
ST-LINK/V2-1 firmware upgrade
The ST-LINK/V2-1 embeds a firmware upgrade mechanism for in-situ upgrade through the
USB port. As the firmware may evolve during the life time of the ST-LINK/V2-1 product (for
example new functionalities, bug fixes, support for new microcontroller families), it is
recommended to visit the
www.st.com
website
before starting to use the STM32091C-EVAL
board and periodically, in order to stay up-to-date with the latest firmware version.
2.2
Board power supply
STM32091C-EVAL evaluation board is designed to be powered by 5 V DC power supply
and to be protected by PolyZen from wrong power plug-in event. It is possible to configure
the evaluation board to use any of the following three sources for the power supply:
•
5 V DC power adapter connected to CN16 (the Power jack on the board showed as
PSU
on JP15 silkscreen and called E5V). The external power supply is not provided
with the board.
•
5 V DC power from CN12 (the USB Type-B connector of ST-LINK/V2-1, that is showed
as STlk on JP15 silkscreen and called U5V). If the USB enumeration succeeds (as
explained below), the ST-LINK U5V power is enabled, by asserting the PWR_EN pin.
This pin is connected to a power switch (ST890), which powers the board. This power
switch features also a current limitation to protect the PC in case of short-circuit on the
board. If overcurrent (more than 600 mA) happens on board, the LED LD10 is lit.
•
5 V DC power from CN7 (the extension connector for daughterboard, that is showed as
D5V on JP15 silkscreen).
STM32091C-EVAL evaluation board can be powered from ST-LINK USB connector CN12
(U5V), but only the ST-LINK part has the power before USB enumeration, because the host
PC only provides 100 mA to the board at that time. During the USB enumeration, the
STM32091C-EVAL board asks for the 300 mA power to the host PC. If the host is able to
provide the required power, the enumeration finishes by a “SetConfiguration” command and
then, the power transistor U23 (ST890) is switched ON, the red LED LD5 is turned ON, thus
STM32091C-EVAL board can consume maximum 300 mA current, but not more. If the host
is not able to provide the requested current, the enumeration fails. Therefore the ST890
(U23) remains OFF and the STM32 part including the extension board will not be powered.
As a consequence the red LED LD5 remains turned OFF. In this case it is mandatory to use
an external power supply as extra power supply.
E5V (from PSU) or D5V can be used as external power supply in case the current
consumption of the STM32091C-EVAL board exceeds the allowed current on the USB. In
this condition it is still possible to use the USB for communication, for programming or
debugging only, but it is mandatory to power the board first using E5V or D5V, then
connecting the USB cable to the PC. Proceeding this way the enumeration succeeds thanks
to the external power source.
The following power sequence procedure must be respected:
4. Connect jumper JP15 for PSU or D5V side
5. Check that JP18 is removed
6. Connect the external power source to PSU or D5V (daughterboard mounted)
7. Check red LED LD5 is turned ON
8. Connect the PC to USB connector CN12
