BPK-000 v8 is a drop-in replacement for previous versions. Here's a quick visual comparison of versions 7 and 8:
- The 5-pin power/serial header is unchanged, and located in the same position relative to the LCD-connection pads.
- The DIP switch for configuring LINES and BPS settings has been replaced by cuttable jumpers (defaulting to multiline, 9600bps). For 1-line displays, cut the LINES jumper; for 2400bps, cut the BPS jumper.
- Pins 1-14 of the LCD connections are unchanged. Pins 15 and 16 have been added to allow hookup of common LED backlights (pin 15= A/+5V, pin 16=K/GND).
- Pads have been added for a series resistor in the GND leg of the LED backlight circuit. Installing a resistor (typical values 10-100Ω) here will complete the backlight circuit.
The LCD Serial Backpack circuit was originally built around the PIC16C54 microcontroller. It was later migrated to PIC16C620 to take advantage of in-circuit programming and built-in low-voltage reset options that simplified manufacturing.
Version 8 is based on the PIC16F54, the flash-memory version of the 'C54. Version 8 uses an external low-voltage reset, a Microchip MCP131T-450E/TT.
The startup delay with the external reset is slightly longer (+70ms) than the v7's built-in reset.
Firmware: No Changes
The firmware was not changed during this update; it is identical to the PIC16(C/F)54 devices the we sell for OEM integration. It is functionally the same as the PIC16C620 version.