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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html><head> <title></title> <link rel="stylesheet" media="screen" type="text/css" href="./style.css" /> <link rel="stylesheet" media="screen" type="text/css" href="./design.css" /> <link rel="stylesheet" media="print" type="text/css" href="./print.css" /> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /></head><body><a href=start.html>start</a></br><div class="toc"><div class="tocheader toctoggle" id="toc__header">Table of Contents</div><div id="toc__inside"><ul class="toc"><li class="level1"><div class="li"><span class="li"><a href="#blackfin_twi_i2c_adaptor_cards" class="toc">Blackfin TWI/I2C Adaptor Cards</a></span></div><ul class="toc"><li class="level2"><div class="li"><span class="li"><a href="#stamp_twi_adaptor_card" class="toc">STAMP TWI Adaptor Card</a></span></div></li><li class="level2"><div class="li"><span class="li"><a href="#stamp_twi_keypad_card" class="toc">STAMP TWI Keypad Card</a></span></div></li><li class="level2"><div class="li"><span class="li"><a href="#stamp_lcd_adaptor_card" class="toc">STAMP LCD Adaptor Card</a></span></div></li></ul></li><li class="level1"><div class="li"><span class="li"><a href="#blackfin_twi_i2c_drivers" class="toc">Blackfin TWI/I2C Drivers</a></span></div></li><li class="level1"><div class="li"><span class="li"><a href="#blackfin_twi_i2c_hardware" class="toc">Blackfin TWI/I2C Hardware</a></span></div></li></ul></div></div><h1><a name="blackfin_twi_i2c_adaptor_cards" id="blackfin_twi_i2c_adaptor_cards">Blackfin TWI/I2C Adaptor Cards</a></h1><div class="level1"></div><!-- SECTION [1-47] --><h2><a name="stamp_twi_adaptor_card" id="stamp_twi_adaptor_card">STAMP TWI Adaptor Card</a></h2><div class="level2"><p> <a href="media/twi_ad_card.jpg" class="media" target="_blank" title="twi_ad_card.jpg"><img src="media/twi_ad_card.jpg" class="media" alt="" /></a></p><p>This card serves several purposes. It provides ease of connectivity to to all kind of I2C capable devices. Usually TWI/I2C is used as a configuration interface for a attached devices, or for user interfaces. Such as Keypads, LEDs, Buttons, Touchscreens, Display Devices, etc. </p><p>The Bus length formed by Adaptor Card can exceed several inches, because only required signals are connected to the bus. The card provides 3.3 Volt and 5 Volt supply, as well as two sets of 3.3V and 5 Volt I2C signals, namely SDA (Data), SCL (Clock) In addition 3 other Blackfin General Purpose IOs <strong>can</strong> be connected to the TWI/I2C Adaptor connector, unused signal - maybe used by other a High-Speed devices on-board or by other Blackfin STAMP adaptor cards are not extended - signal integrity issues are therefore less likely to happen.</p></div><!-- SECTION [48-932] --><h2><a name="stamp_twi_keypad_card" id="stamp_twi_keypad_card">STAMP TWI Keypad Card</a></h2><div class="level2"><p> <a href="media/keypad_lr.jpg" class="media" target="_blank" title="keypad_lr.jpg"><img src="media/keypad_lr.jpg" class="media" alt="" /></a> <a href="media/keypad_back_lr.jpg" class="media" target="_blank" title="keypad_back_lr.jpg"><img src="media/keypad_back_lr.jpg" class="media" alt="" /></a></p><p>This card only utilizes PCF8574 Remote 8-bit I/O expander for I2C-bus</p><p>This device consists of an 8-bit quasi-bidirectional port and an I2C-bus interface. The PCF8574 has a low current consumption and includes latched outputs with high current drive capability for directly driving LEDs. It also possesses an interrupt line (INT) which can be connected to the interrupt logic of the Blackfin Processor. By sending an interrupt signal on this line, the remote I/O can inform the Blackfin Processor if there is incoming data on its ports without having to communicate via the I2C-bus. This means that the PCF8574 can remain a simple slave device.</p><p>It’s therefore perfectly suited to scan a Keypad 4×4 matrix, resulting in 8-bit. One GPIO is used to inform Blackfin - that data is available. While definetly! the user still has the finger on the button.</p><p><a href="blackfin_twi_keypad_driver.html" class="wikilink1" title="blackfin_twi_keypad_driver.html">Blackfin TWI Keypad Driver</a></p></div><!-- SECTION [933-1896] --><h2><a name="stamp_lcd_adaptor_card" id="stamp_lcd_adaptor_card">STAMP LCD Adaptor Card</a></h2><div class="level2"><p> <a href="media/lcd_disp_card_less_stuffed.jpg" class="media" target="_blank" title="lcd_disp_card_less_stuffed.jpg"><img src="media/lcd_disp_card_less_stuffed.jpg" class="media" alt="" /></a></p><p>There are many ways to do a simple user interface. One is to use a simple character based LCD module. Most of these modules (sometimes available for less than 4$) feature a Hitachi HD44780 compatible interface. This card provides ease of connectivity to most of these available modules.</p><p>It also features the PCF8547 IO expander. In addition a AD5252 is used for TWI/I2C contrast control and backlight intensity control. </p><ul><li class="level1"><div class="li"> <a href="blackfin_twi_lcd_hd44780_based_driver.html" class="wikilink1" title="blackfin_twi_lcd_hd44780_based_driver.html">Blackfin TWI LCD (HD44780 based) Driver</a></div></li><li class="level1"><div class="li"> <a href="blackfin_ad5252_twi_i2c_digital_potentiometer_driver.html" class="wikilink1" title="blackfin_ad5252_twi_i2c_digital_potentiometer_driver.html">Blackfin AD5252 TWI/I2C Digital Potentiometer Driver</a></div></li></ul></div><!-- SECTION [1897-2501] --><h1><a name="blackfin_twi_i2c_drivers" id="blackfin_twi_i2c_drivers">Blackfin TWI/I2C Drivers</a></h1><div class="level1"><ul><li class="level1"><div class="li"> <a href="blackfin_twi_keypad_driver.html" class="wikilink1" title="blackfin_twi_keypad_driver.html">Blackfin TWI Keypad Driver</a></div></li><li class="level1"><div class="li"> <a href="blackfin_twi_lcd_hd44780_based_driver.html" class="wikilink1" title="blackfin_twi_lcd_hd44780_based_driver.html">Blackfin TWI LCD (HD44780 based) Driver</a></div></li><li class="level1"><div class="li"> <a href="blackfin_ad5252_twi_i2c_digital_potentiometer_driver.html" class="wikilink1" title="blackfin_ad5252_twi_i2c_digital_potentiometer_driver.html">Blackfin AD5252 TWI/I2C Digital Potentiometer Driver</a></div></li></ul></div><!-- SECTION [2502-2687] --><h1><a name="blackfin_twi_i2c_hardware" id="blackfin_twi_i2c_hardware">Blackfin TWI/I2C Hardware</a></h1><div class="level1"><p> Hardware: <a href="http://blackfin.uclinux.org/frs/?group_id=7&release_id=260" class="urlextern" title="http://blackfin.uclinux.org/frs/?group_id=7&release_id=260" rel="nofollow">TWI Interface Cards (Keypad, LCD, GPIO)</a> </p></div><!-- SECTION [2688-] --></body></html>⌨️ 快捷键说明
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