Revision 1.1
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DLP-IO16 Development System
GENERAL DESCRIPTION
The DLP-IO16 consists of a Universal Serial Bus (USB) Interface, a PIC 16F84A (target)
microcontroller and a Flash programming system. The USB interface is designed around FTDI’s
FT8U245AM and is used for both the Flash download process and host communications
(16F84A to Host PC) at run time. The target processor (16F84A) will hold 1024 14-bit words of
ROM, 68 bytes of RAM and 64 bytes of EEPROM, none of which is used by the on-board Flash
Programming system. The Flash programming system is comprised of a PIC 16F872 and a 12.5-
volt DV-DC converter and is used exclusively to perform the download process.
Hex file data can be written directly into the 16F84A’s Flash memory without the need for an
external device programmer. PC application software that runs under Windows 98/2000 is
available from dlpdesign.com as a free download that performs the Flash download process.
The DLP-IO16 connects to the user’s hardware via 8 buffered digital inputs and 8 latched digital
outputs. The digital outputs are implemented using an SN74HC374 and are specified to drive up
to 15 LSTTL loads each. The digital inputs also use a SN74HC374 to latch the incoming digital
data. The DLP-IO26 provides a larger (8K) Flash ROM and more I/O port lines for interfacing
to target electronics. Refer to the datasheet for the DLP-IO26 for additional details.
USB
Interface
Power
Isolation
Switches
Download
Microcontroller
PIC16F872
Target
Microcontroller
PIC16F84A and
Buffers
Input/Output Connector
12.5 Volt
DC-DC
Converter
