LPC1224_BO_SRM
Board v0.3
Fig 11 – User Led
Note
: The PIO1_4 and PIO1_5 pins are not PWM capable so it’s not possible to create shades
between red and green without using a lot of processing power.
After reset the ISP button can be used by the user to any purpose. It’s state can be read on pin PIO0_12 (pin
27).
4.4 USB to UART bridge
Fig 12 – USB to UART bridge
In order to ease the development process and the use of the module we added a USB to UART bridge on-board.
This bridge is made by a FTDI FT230XS chip. It provides a 3.3V regulated voltage for the module and is well
supported on most operating systems so there is usually no configuration required to use it as a serial line on the
host development system, removing the need of any additional power source or of specific hardware to program the
LPC1224 micro-controller and communicate with the module.
The FTDI chip controls two "activity" leds for Rx (D3, the green one) and Tx (D4, orange one) data over the
serial link.
Removing jumpers J3 and J4 disconnects the USB to UART bridge from the LPC1224 micro-controller.
Techno-Innov - DomoTab
http://www.techno-innov.fr
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