DLP-245PL-G DLP Design Inc, DLP-245PL-G Datasheet - Page 5

• Manufacturer Part Number: DLP-245PL-G
• Description: MOD USB-MCU FT245RL W/18LF8722
• Manufacturer: DLP Design Inc

Specifications of DLP-245PL-G

• Module/board Type: Development Board
• Interface Type: USB
• Data Bus Width: 8 bit
• Operating Supply Voltage: 5 V
• Product: Interface Modules
• For Use With/related Products: USB
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 813-1005

TOKEN I/O
The 18LF8722 microcontroller on the DLP-245PL-G is shipped from the factory preprogrammed
with firmware that provides rudimentary access to the port pins via either the VCP or DLL drivers.
Features include the ability to read and write individual port pins as well as 8-bit port reads and
writes.
The firmware in the DLP-245PL-G also provides access to the 18LF8722’s A/D converter,
EEPROM memory, and communications with digital temperature-sensing devices.
Commands sent to the Token I/O firmware must adhere to a specific communications protocol.
Each command sequence contains the following information:
The checksum is computed by exclusive-OR-ing every byte in the string. If the same checksum
is calculated by the 18LF8722 upon receipt of the packet, then a single-byte reply of 0x55 is
returned to the host. In the event of a checksum error, the 18LF8722 will return an error code of
0xAA. For example, setting port PIN_A1 high would require the following string of bytes:
0x03, 0xA6, 0x2D, 0x01, 0x89
Definition of the Bytes:
0x03 – Number of bytes in command (checksum excluded)
0xA6 – Command for set port pin high/low
0x29 – Affected port pin
0x01 – Desired state of port pin
0x8D – Checksum of previous 4 bytes
The port pins equate to hexadecimal numeric constants as defined below:
PORT A:
PIN_A0 0x2C, PIN_A1 0x2D, PIN_A2 0x2E,
PIN_A3 0x2F, PIN_A4 0x30, PIN_A5 0x31
PORT B:
PIN_B0 0x34, PIN_B1 0x35, PIN_B2 0x36, PIN_B3 0x37,
PIN_B4 0x38, PIN_B5 0x39, PIN_B6 0x3A, PIN_B7 0x3B
Byte 0:
Byte 1:
Byte 2…n-1:
Byte n:
Number of bytes in command sequence
Command
Parameter/Data bytes
Checksum
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