16f877 Unused Pins

[hvacrtech]

I use LCDOUT with DB4-DB7 on PORTB.0-PORTB.3, RS on PORTC.1, Ebit on PORTC.0 on 16F886. Starting BIT is set to 0. Will setting TRISB and TRISC even not set correctly can damage the LCD as well the PIC itself?

example TRISB=00000000 and TRISC=00001111 as used before, works fine till I noticed something that TRISC shows last four inputs and I changed it to TRISC=00000000, the result is damaged. all are set for DIGITAL Modes (ANSEL).

Does it have to have TRIS set correctly for use with LCD?

I have about ten units running fine with TRISB=00000000 and TRISC=00001111 working fine, then the two units failed with modified TRIS's TRISC=00000000. Maybe the TRISB needs to be 11110000 and TRISC set to 00000011?