Curso Picaxe

AXE033 SERIAL/I2C LCD

The serial LCD and clock module allows microcontroller systems (e.g. PICAXE) to visually output user instructions or readings, without the need for a computer. This is especially useful when working, for example, with analogue sensors, as the analogue reading can easily be displayed on the LCD module. All LCD commands are transmitted serially via a single microcontrollerpin using the serout command. e.g. to print the text ‘Hello’ the command is simply: serout B.7,N2400,(“Hello”) The module can also store 7 programmable pre-defined messages to save memory space usage within the PICAXE system. The optional low-cost clock upgrade provides a real-time clock and programmable alarm output. The LCD can show the current date and time on it’s display, and the alarm outputcan be programmed to trigger at any period between 10 seconds and 1 year. The clock has a lithium coin cell backup that maintains the time for up to ten years when the main power supply is removed.

Key Features:
1. 16x2 LCD Alphanumeric Display 2. Simple serial (1 wire) connection to microcontroller (2400,N,8,1). 3. Optional i2c interface. 4. 7 Programmable pre-defined messages 5. Smallfootprint (almost same size as the LCD). 6. Optional low-cost clock upgrade, providing • • • • Real Time Clock Programmable Alarm Output 1Hz pulse output 10 year battery backup

For the full datasheet please see www.picaxe.com/docs/axe033.pdf

revolution

© copyright 2003-12 Revolution Education Ltd.

Web: www.picaxe.com

AXE033.pmd v4.4

SERIAL/i2c LCD AND CLOCK

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Which Mode?(serial or i2c)
Most users will use the module in the default serial mode. The only main reason to use it in i2c mode is if you wish to read the time/data from the DS1307 clock upgrade directly into the PICAXE chip. In all othe cases the serial mode should be used. In i2c mode the LCD module acts as a ‘dumb’ i2c slave device. The clock and alarm functions are not available - all clock and alarmfunctions must be carried out by the PICAXE part itself. See Section 1 for construction and assembly details. A jumper link (J1) is required for i2c mode. See Section 2 on pages 6-7 for i2c connection details and samples. Further information about i2c protocol and interfacing can be found in the ‘i2c Tutorial’ help file. It is assumed that the user has already read this help file. See Section 3 on pages8-15 for serial connection details and samples.

revolution

© copyright 2003-12 Revolution Education Ltd.

Web: www.picaxe.com

AXE033.pmd v4.4

SERIAL/i2c LCD AND CLOCK

3

Section 1 - Construction and Kit Contents
• • • • pre-populated PCB 16x2 alphanumeric display (brand may vary) bag of 4 support posts and 3x 10 pin headers 5R6 and 0 ohm resistors (backlit LCD display AXE033Bonly)

The LCD is supplied loose so that it can be either fitted directly to the board, or connected via a longer ribbon cable connection if desired. The following instructions explain how to fit the LCD directly to the board (track side) and presume the user is confident at soldering.

Connecting the LCD
1. Snap one header into a 4 and 6 way section. AXE033 (LCD) or AXE033Y (OLED) Place theshort end of the 4 way section, with another 10 way header, through the holes labelled 1-14 on the pcb (from the track side of the PCB, so that the top of the short end shows on the component side). Note the extra holes marked A and K and resistor RB are only used on LCDs with LED backlights (the LCD in the kit does not have a backlight and so these connections are not required). AXE033B (LCD withbacklight) Place the short end of the 6 way section, with another 10 way header, through the holes labelled 1-16 (or 1-14,A,K) on the pcb (from the track side of the PCB, so that the top of the short end shows on the component side). Solder a resistor in the position RB. The value of the resistor depends on the power supply - for 4.5V use the zero ohm (single black band) resistor, for 5V use...