Usb Uart A - Mikroe EasyMx PRO v7a Manual

USB-UART A
The UART (universal asynchronous receiver/trans mitter) is one of the most common
ways of exchanging data between the MCU and peripheral components. It is a serial
protocol with separate transmit and receive lines, and can be used for full-duplex
communication. Both sides must be initialized with the same baud rate, otherwise the
data will not be received correctly.
Modern PC computers, laptops and notebooks are no longer equipped with RS-232
connectors and UART controllers. They are nowadays replaced with USB connectors and
USB controllers. Still, certain technology enables UART communication to be done via
USB connection. Controllers such as FT232RL from FTDI® convert UART signals to the
appropriate USB standard.
USB-UART A communication is being done through a FT232RL controller, USB
connector (CN22), and microcontroller UART module. To establish this connection,
you must connect RX and TX lines of the microcontroller to the appropriate input and
output pins of the FT232RL. This selection is done using DIP switches SW12.1 and
SW12.2.
VCC-3.3V
U2
PA9 TX-FTDI1 1
TXD OSCO
PA10 RX-FTDI1 2
DTR# OSCI
3
RTS# TEST
4
VCCIO AGND
5
RXD NC
6
RI# CBUS0
7
GND CBUS1
FT232RL
8
NC GND
9
DSR# VCC
SW12 10
DCD# RESET#
11
CTS# GND
12
CBUS4
3V3OUT
13
CBUS2 USBDM
14
CBUS3 USBDP
FT232RL
VCC-5V VCC-3.3V VCC-3.3V
R14 R15
2K2 4K7
28
27
26 RX TX
25
24
LD69 LD70
23 RX-LED1
22 TX-LED1
D-
R18
21 D+
4K7
20
19
R83
18
5.1k
17
R84 27
16 FTDI1-D_N
15 FTDI1-D_P
R85 27
C11
R21
100nF
10K
D8
1 6
D+
I/O1 I/O1
2 5
GND
GND VBUS
3 4
D-
I/O2 I/O2
USBLC6-2P6
Enabling USB-UART A
USB-VBUS
B1A12
GND
B4A9
VBUS
B8
SBU2
B7
DN2
B6
DP2
B5
CC2
R82
A8
SBU1
A7
5.1k
DN1
A6
DP1
A5
CC1
In order to enable USB-UART A
A1B12
GND
A4B9
VBUS
communication, you must push
CN22
USB TYPE-C
SW12.1 (PA9) and SW12.2 (PA10)
D+
USB-VBUS to ON position. This connects the
D-
TX and RX lines to PA9 and PA10
microcontroller pins and its UART
module.
E a s y M x P R O v 7 a U s e r M a n u a l