Mikroe Go to Cloud click User manual

U S ER M ANU A L
Go to Cloud
(G2C) click
The WiFi IoT gateway Click board™which
connects your IoT devices with the Click
Cloud service provided by MikroElektronika.
Simple and reliable.

Page 2
Nebojsa Matic
General Manager
I want to express my thanks to you for being interested in our products
and for having confidence in MikroElektronika.
The primary aim of our company is to design and produce high quality
electronic products and to constantly improve the performance thereof in
order to better suit your needs.
To our valued customers

Table of Contents
Introduction to Go to Cloud (G2C) click 4
mikroBUS™pins 7
Onboard indicators and LED indicators 8
Pins description 8
UART interface – configuration 9
Boot-up sequence 10
Firmware update 12

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Introduction to Go to Cloud (G2C) click
Go to Cloud (G2C) click is composed of two main components:
∫MK64FN1M0VDC12, a 32-bit ARM® Cortex® M4 microcontroller, from NXP
∫ESP WROOM-02, a Wi-Fi connector module, from Espressif systems
The ESP-WROOM-02 is used as the connector module which can establish a link with the Click cloud service over the Internet.
It is an all-in-one solution, with the complete Wi-Fi stack on-board, which allows a very simple operation. This feature, along
with the proven reliability, small form-factor, and low count of components it requires, makes the ESP WROOM-02 module
an ideal solution for using it on the Go to Cloud (G2C) click.
The ESP-WROOM-02 module uses the UART communication interface, and it can be controlled by using simple AT
commands. However, the MK64FN1M0VDC12 MCU is added too, introducing an additional application layer, exposing
only a set of commands that allow connection with the Click Cloud, reducing the possibility of errors and failures due
to wrongly set connection parameters and simplifying HOST MCU application. The MCU is also used to drive status
LEDs, which are used to indicate a successful connection to the Internet, a successful connection with the Click Cloud
service, as well as some other types of indication.

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Figure 2:
MK64FN1
M0VDC12 MCU
Figure 1:
ESP-WROOM-02
Finally, there is a micro USB connector, which is used to update the firmware of the Go to Cloud (G2C) click. The
firmware update is simple, error-proof, and straight-forward. More information about the update procedure can be
found in this manual.

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VCC-3.3
VOUT-3.3 VOUT-3.3 VOUT-3.3
IO14
IO12
IO13
IO15
IO2
ESP_RST
ESP_TXD
ESP_RXD
C3 10µF
VCC-3.3
VOUT-3.3
ESP_EN
LD1
PWR
18
18
17
17
16
16
15
15
14
14
13
13
12
12
11
11
10
109
8
7
6
5
4
3
2
1
GND
IO0
IO2
IO15
IO13
IO12
IO14
EN
3.3V
IO4
RXD
TXD
GND
IO5
RST
TOUT
IO16
GND
ESP-WROOM-02
U2
JTAG_TCLK
JTAG_TDI
JTAG_TDO JTAG_TMS
MCU_RST
MCU_RST
UART0_RTS
UART0_CTS
UART0_RX
UART0_TX
ESP_TXD ESP_RXD
ESP_RST
ESP_EN
UART0_TX
UART0_RX
UART0_CTS
JTAG_TMS
JTAG_TCLK
JTAG_TDO
JTAG_TDI
VOUT-3.3 VOUT-3.3
MCU_RST
R6
10k
R7
10k
R8
10k
R9
10k
R14
10k
R15
10k
C4 0.10µF
C2
0.10µF
UART0_RTS
Y2
32.768kHz
C8
12pF
C9
12pF
LD3
STAT
STATUS_LED
LD4
CONN
CONN_LED
CONN_LED
R1
1k
R3
1k
12
34
56
78
910
J1
VCC-5V
VCC-5V
STATUS_LED
IO0
IO0
R13
10k
IO15 IO13
R4
1k
C3
D11
E11
F11
E1 D1
D2
C1
C2
B1
A9
A10
A1
B2
A2
A3 B3 D3
D4
A4 B4
C4
A6
A5
B5
D5
B6
C5
C6
D6
A7
A8
D7
C7
B7
L2
L1
K2
K1
E2
E7
F7
A11
C11
K10
L10
H2
H1
L6
G7
E6
F3
G4
H7
K3
H4
E4
E3
F4
L11
K11
L7
B11
G2
G1
F2
F1
J2
J1
H10
MK64FN1M0VDC12
J11
H11
G11
G10
G9
G8
E10
D10
C10
B10
E9
D9
C9
F10
F9
F8
E8
B9
D8
C8
ADC0_SE16/CMP1_IN2/AD C0_S E21
ADC1_SE16/CM P2_IN2/AD C0_SE22
NC
NC
PTE0
PTE1/LLWU_P0
PTA4/LLWU_P3
DAC0_OUT/CMP1_IN3/ADC0_S E23
VREF _OUT/CMP1_IN5 CMP0_IN5/ADC 1_SE18
PTA0
PTA1
PTA2
PTA3
DAC1_OUT/CMP0_IN4 CMP2_IN3/ADC 1_SE23 XTAL32
PTB17
PTB16
PTB11
PTB19
PTB10
PTB9
PTB1
LLWU_P5/PTB0
NC
PTB13
PTC0
PTB23
PTB22
PTB21
PTB20
PTB18
VSS
ADC0_DM0/ADC1_DM3
ADC0_DP1
VREGIN
VOUT33
USB0_DM
USB0_DP
VSS
PTA15
PTE5
VDD
PTE3
VREF H
LLWU_P6/PTC1
PTC2
RTC_WAKEUP_B
PTB12
ADC0_DP0/ADC1_DP3
ADC1_DM1
ADC1_DP1
ADC0_DM1
PTE24
PTE25
PTA16
PTA10
EXTAL32
VBAT
PTA5
VREF L
VDDA
VDD
PTA11
PTB3
VSS
VDD
PTE6
VSSA
VSS
PTA14
PTB2
ADC1_DM0/ADC0_DM3
ADC1_DP0/ADC0_DP3
PTE4/LLWU_P2
PTE2/LLWU_P1
PTA12
PTA13/LLW U_P4
VSS
PTA17
VDD
PTA18
PTA19
RESET_b
PTA29
LLWU_P7/PTC3
LLWU_P9/PTC5
PTC7
LLWU_P10/PTC6
LLWU_P8/PTC4
LLWU_P14/PTD4
PTD3
PTD1
LLWU_P14/PTD6
LLWU_P12/PTD0
PTC19 PTC16
PTC15
PTD11
PTD10
PTD9 PTD8
PTD7
PTD5
PTD12
PTD13
PTC18 PTC17 PTC10
PTC8
PTC9
LLWU_P11/PTC11
PTC12
PTC13
PTC14
PTD14
PTB6
LLWU_P13 /PTD2
PTB8
PTB7
PTD15
B8
PTE26
J10
L9
K9
L8
K4
L5
K6
F6
G6
J9
G3
J7
H8
J6
H6
J5
H5
J3
H3
L3
K5
L4
F5
G5
E5
K7
J8
H9
K8
J4
U1 MK64FN1M0VDC12
C5
2.2µF
R5
10k
VOUT-3.3
C1
2.2µF
VCC-5V
AN
RST
CS
SCK
MOSI
MISO
+3.3V
GND
PWM
INT
RX
TX
SCL
SDA
+5V
GND
MIKROBUS DEVICE CONN
VOUT-3.3
VCC-5V
1
2
3
4
5
ID
D+
D-
VBUS
GND
6
CN1
TVS1TVS2
R11 27
R12 27
R10
1M
LD2
USB
VCC-3.3
VCC-USB
VCC-USB
R2
1k
GP0
GP1
GP0 GP1
D1
PMEG3010ER,115
D2
PMEG3010ER,115
Y1
12MHz
C6
12pF
C7
12pF
Figure 3: Main Schematic

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mikroBUS™pins
An additional JTAG interface in the form of 2x5 pin header is used only during the production phase for the upload of
the initial firmware and it should not be used by the user, as it may lead to malfunction of the Go to Cloud (G2C) click
due to an internal firmware damage.

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Onboard indicators and LED indicators
NOTE: The Go to Cloud (G2C) click requires both 3.3V and 5V for a proper operation.
Pins description:
∫ RST - Hardware reset - (INPUT) This pin is used to reset the MCU. This pin is internally pulled up to a HIGH logic level. Driving
this pin to a LOW logic level for 50 ms, a reset function will be performed. After each reset cycle, the complete boot sequence
of the Go to Cloud (G2C) click is repeated.

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∫ CTS - Clear to send [1] - (INPUT) A LOW logic level on this pin means that HOST MCU
is ready to receive data sent from Go to Cloud (G2C) click.
∫ RTS - Request to send [1] - (OUTPUT) A LOW logic level on this pin means that the Go to Cloud (G2C) click
is ready to accept incoming data from the host MCU. There is also a secondary function of this pin: if set to a HIGH
logic level during the boot-up sequence, the five-second bootloader timeout will be completely skipped, allowing for
a faster start of the Go to Cloud (G2C) click. More information about the secondary function of this pin is provided in the
Boot-up section of this manual.
∫ GP0, GP1 - General purpose pins[1] - (INPUT) A LOW logic level on this pin means that HOST MCU
is ready to receive data sent from Go to Cloud (G2C) click.
[1] The current version of the firmware (ver.F091) does not have these options implemented yet, but they are
planned to be added in future updates.
UART interface – configuration:
∫Baud rate: 57600
∫Data bits: 8
∫Parity: NO
∫Stop bit: 1

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The complete control of the Go to Cloud (G2C) click is done over the UART interface, by using AT commands. The list
of the available AT commands, along with the explanation and example for each of them can be found in the
AT Command Manual.
The Go to Cloud (G2C) click firmware accepts AT commands, which can be sent over the UART interface pins of
the mikroBUS™, either from a terminal application on a personal computer (with the addition of the USB-to-UART
adapter) or from the host MCU. When transmitting the AT command string, a timing interval between consecutive
characters should not exceed 5 seconds. The timing interval greater than 5 seconds is considered as the EOL for any
AT command (end-of-line), and the received command will be parsed as such.
More information about all the available AT commands with the detailed explanation can be found in the AT Commands Manual.
UART interface – configuration:
After the power-on, the Go to Cloud (G2C) click will start in the bootloader mode, which will be terminated after 5
seconds. During these 5 seconds, the MK64F MCU onboard the Go to Cloud (G2C) click will be visible to the USB
HID Bootloader application, allowing its firmware to be updated. When the connection with the USB HID Bootloader
application is established, it will take over the control of the Go to Cloud (G2C) click and will keep it in the bootloader

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mode. If there is no response from the USB HID Bootloader application while the Go to Cloud (G2C) click is in the
bootloader mode, the normal operation of the Go to Cloud (G2C) click will be resumed and the MK64F MCU will not be
visible for the USB HID Bootloader application anymore.
After a connection with the USB Bootloader application is established, the STAT LED will be turned on and it will stay
that way as long as the bootloader mode is active. Leaving the bootloader mode will be indicated by the CONN LED,
which will blink once, while the STAT LED will be turned off.
The bootloader mode will be automatically initiated after each power-on event, leading to a five-second startup
delay. To skip the bootloader mode completely and boot-up directly into the normal mode, the CTS pin can be set to
a HIGH logic level after the restart, for at least 100ms. This prevents the five-second delay during the power on if the
firmware update was not intended, shortening the boot-up time before the G2C click is ready to be used.
During the boot-up sequence, the default configuration values will be restored from the internal non-volatile memory.
More details about storing and restoring the default configuration parameters can be found in the AT Commands
Manual.
The end of the boot-up sequence will be indicated by a single blink of both the STAT and CONN LEDs, simultaneously.
NOTE: After leaving the bootloader, a delay of at least 3 seconds has to be made, allowing the connector module to reboot properly.

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Firmware update
Figure 4: USB HID Bootloader connected to the Go to
Cloudd (G2C) click
The G2C click is shipped with the latest version of
firmware. However, the firmware will be continuously
improved in the future. Therefore, the Go to Cloud (G2C )
click has a firmware update option, in a form of a micro
USB connector (CN1) and an implementation of the HID
bootloader within the firmware itself.
To properly update the firmware, please use the provided
micro USB connector (CN1) with the HID bootloader
application and a proper firmware file. The JTAG 2x5-pin
header (J1) is not to be used for uploading the update
since it can destroy the base firmware and render the
G2C click inoperable. It is used only for the initial firmware
update during the production. The Go to Cloud (G2C )click
is shipped with this header unpopulated.
The firmware update can be done by using the USB HID
Bootloader application. After a USB cable is connected to
the micro USB connector on the Go to Cloud (G2C )click,
the application will detect the onboard MK64F MCU, as
displayed on the picture below:

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Note that there is a five seconds timeout interval during which the Go to Cloud (G2C )click operates in a firmware update
mode as explained in the Boot-up sequence section of this manual. After this, the Go to Cloud (G2C )click is restarted and
will continue running in a normal mode, completely skipping the bootloader, and will be undetectable for the HID bootloader
application. If this happens, it is necessary to disconnect the USB cable and connect it again, initiating another five seconds
interval.
After the MCU of the Go to Cloud (G2C )click is detected as on the picture above, an appropriate HEX file with a proper
firmware version should be selected by clicking on the Browse for HEX button. This will open a file selection window, where
you can browse for the updated firmware file with the .hex extension. Once selected, the programming process can be
started by clicking the Begin uploading button. The programming process should take up to 60 seconds. If it takes longer, or
the process is interrupted during the update, it should be repeated from the beginning.

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DISCLAIMER
All the products owned by MikroElektronika are protected by copyright law and international copyright treaty. Therefore, this manual is to be treated as any other copyright material.
No part of this manual, including product and software described herein, may be reproduced, stored in a retrieval system, translated or transmitted in any form or by any means,
without the prior written permission of MikroElektronika. The manual PDF edition can be printed for private or local use, but not for distribution. Any modification of this manual is
prohibited. MikroElektronika provides this manual ‘as is’ without warranty of any kind, either expressed or implied, including, but not limited to, the implied warranties or conditions of
merchantability or fitness for a particular purpose. MikroElektronika shall assume no responsibility or liability for any errors, omissions and inaccuracies that may appear in this manual.
In no event shall MikroElektronika, its directors, officers, employees or distributors be liable for any indirect, specific, incidental or consequential damages (including damages for loss of
business profits and business information, business interruption or any other pecuniary loss) arising out of the use of this manual or product, even if MikroElektronika has been advised
of the possibility of such damages. MikroElektronika reserves the right to change information contained in this manual at any time without prior notice, if necessary.
HIGH RISK ACTIVITIES
The products of MikroElektronika are not fault – tolerant nor designed, manufactured or intended for use or resale as on – line control equipment in hazardous environments
requiring fail – safe performance, such as in the operation of nuclear facilities, aircraft navigation or communication systems, air traffic control, direct life support machines
or weapons systems in which the failure of Software could lead directly to death, personal injury or severe physical or environmental damage (‘High Risk Activities’).
MikroElektronika and its suppliers specifically disclaim any expressed or implied warranty of fitness for High Risk Activities.
TRADEMARKS
The MikroElektronika name and logo, mikroC, mikroBasic, mikroPascal, Visual TFT, Visual GLCD, mikroProg, Ready, MINI, mikroBUS™, EasyPIC, EasyAVR, Easy8051, Click boards™and
mikromedia are trademarks of MikroElektronika. All other trademarks mentioned herein are property of their respective companies.All other product and corporate names appearing in
this manual may or may not be registered trademarks or copyrights of their respective companies, and are only used for identification or explanation and to the owners’ benefit, with
no intent to infringe.
The FTDI Chip® and Windows® logos and product names are trademarks of FTDI Chip and Microsoft® in the U.S.A. and other countries.
Copyright © 2019 MikroElektronika. All Rights Reserved.

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