This was one of my first doublesided and surfacemount boards. I made this board using Eagle for layout and then I used BatchPCB to manufacture the board. The board operates correctly, however, if I were to revise it, I would use a larger SMT resistor than the 0402 size. The board will be controlled via I2C from a PIC microcontroller, initially for the pressure sensor and later for other projects.
C1, 2.7nf (2700pf)
R1,R2 = 220 Ohms
; SAA1064 Constants SAA1064ADDRESS EQU B'01110000' ; I2C Address SAA1064CONTROL EQU B'00000111' ; Control, bits 6:4 are for brightness SAA1064SEGDASH EQU B'01000000' ; - SAA1064SEGDP EQU B'10000000' ; . SAA1064SEGJ EQU B'00011110' ; J
;Lookup Table for 7-seg ;TODO Add test to make sure number is 0x0F or below ;DP is Bit 7 SEG_LOOKUP MOVWF Temp,A MOVLW 0x10 SUBWF Temp,A BTFSC STATUS,C RETLW B'11000000' ; Return 0xC0 if over 0x0F - Light up DP and G segments BCF STATUS,C RLCF Temp,w ADDWF PCL,F RETLW B'00111111' ; 0 RETLW B'00000110' ; 1 RETLW B'01011011' ; 2 RETLW B'01001111' ; 3 RETLW B'01100110' ; 4 RETLW B'01101101' ; 5 RETLW B'01111101' ; 6 RETLW B'00000111' ; 7 RETLW B'01111111' ; 8 RETLW B'01100111' ; 9 RETLW B'01110111' ; A RETLW B'01111100' ; B RETLW B'01011000' ; C RETLW B'01011110' ; D RETLW B'01111001' ; E RETLW B'01110001' ; F ;End of Lookup