RPM Tester
I have had a hall effect sensor for awhile that I got for a bike computer project that
I never started.
So I decided to make a RPM tester for my garage sale drill motor finds as an excuse
to play with the part.
I learned that the hall effect sensor latches it's output pin high when exposed to one pole of
a magnet and only latches low when exposed to opposite pole.
So I made a spinner with two magnets across from each other with opposite poles facing
sensor. Each half revolution one of the sensors flies by the sensor.
I count each time the state of the hall effect sensor's output pin changes and divide that
number in half for my revolution count.
Don't know how accurate this thing is, but it will at least give me comparable data on my
drill motor collection.
I never started.
So I decided to make a RPM tester for my garage sale drill motor finds as an excuse
to play with the part.
I learned that the hall effect sensor latches it's output pin high when exposed to one pole of
a magnet and only latches low when exposed to opposite pole.
So I made a spinner with two magnets across from each other with opposite poles facing
sensor. Each half revolution one of the sensors flies by the sensor.
I count each time the state of the hall effect sensor's output pin changes and divide that
number in half for my revolution count.
Don't know how accurate this thing is, but it will at least give me comparable data on my
drill motor collection.
1024 x 734 - 633K
Comments
2010 and it never made the OBEX. Luckily it was still in the forums here: http://forums.parallax.com/showthread.php/117544-128x64-graphics-module?p=855774#post855774
CON _clkmode = xtal1 + pll16x _xinfreq = 5_000_000 clockfreq = ((_CLKMODE - XTAL1) >> 6) * _XINFREQ _1mS = clockfreq / 1_000 'Divisor for 1 mS sdo = 14 'lcd screen sck = 15 rows = 64 cols = 128 lines = 5 thickness = 2 screen = $7000 atr = $7f00 VAR long counter long rotations,old,new,seconds,rpm,temprpm long bufwr,col,row,tx,ty,xmar,ymar 'for lcd screen byte x[lines] byte y[lines] byte xs[lines] byte ys[lines] OBJ vp : "Conduit" timer : "Timer32" gr : "LcdGraphics" PUB Program StartViewport startLCD Main PUB StartViewport vp.config(string("start:dso")) vp.config(string("var:counter,rotations,old,new,seconds,rpm")) vp.share(@counter,@rpm) pub startLCD | i, j, k, kk, dx, dy, pp, pq, rr, numx, numchr,h,text cognew(@st7920,screen) gr.start gr.setup(16, 4, cols/2, rows/2, screen) xmar := 8 byte[atr] := 0 gr.clear gr.colorwidth(3,0) gr.textmode(2,2,6,0) ms(100) 'byte[atr] |= $10 'inversed byte[atr] &= !$10 'normal tx := xmar ty := ymar str16(string(" RPM ")) ' print in Parallax font PUB main timer.init dira[0]~ counter := 0 rotations:=0 rpm := 0 old := 0 timer.mark repeat timer.tick seconds := timer.PassedS new := ina[0] if old<>new rotations++ old := new if timer.PassedS > 2 rotations := rotations / 2 'hall effect sensor flips twice a rotation rpm := rotations * 30 gr.clear 'screen is refreshed every 2 seconds tx := xmar ty := ymar str16(string(" RPM ")) ' print in Parallax font printdecimal(rpm) timer.mark rotations := 0 counter++ pub dp tx -=5 font16(".") tx -=6 pub str16(str) | ch repeat while byte[str] ch := byte[str] if ch == "." dp else font16(ch) str++ pub font16(code) | ptr,ix,iy,ch,sh ptr := ((code/2)<<7) + $8000 sh := code&1 repeat iy from 0 to 31 ' 32 lines ch := long[ptr] ' read combo font for this line ptr +=4 ' update pointer ch >>= sh ' offset for odd or even {endif} repeat ix from 0 to 15 if ch&1 gr.plot(ix+tx-64,32-iy+ty) ch >>= 2 {end} {end} tx += 16 if tx => 128-14 tx := xmar ty -= 32 {endif} pub ftext(bx,by,fontptr,textptr) | yp,xp,ch,bx2,ptr repeat ptr := ((byte[textptr++]-$30)*byte[fontptr+1])+fontptr+4 repeat yp from 0 to byte[fontptr+1]-1 ch := byte[ptr++] >< byte[fontptr] repeat xp from 0 to byte[fontptr]-1 if ch&1 gr.plot(bx+xp,by-yp) ch >>= 1 bx += byte[fontptr]+1 until not byte[textptr] PRI printDecimal(integer) | temp[3] ' Writes a decimal string. byte[@temp][10] := 0 repeat result from 9 to 0 ' Convert number. byte[@temp][result] := ((||(integer // 10)) + "0") integer /= 10 result := @temp ' Skip past leading zeros. repeat while((byte[result] == "0") and (byte[result + 1])) result += 1 str16(result~) ' Print number. DAT ' 5x7 bitmap font font5x7 byte 5,7,0,0 byte %01110 '0 byte %10001 byte %10011 byte %10101 byte %11001 byte %10001 byte %01110 byte %00100 '1 byte %01100 byte %00100 byte %00100 byte %00100 byte %00100 byte %01110 byte %01110 '2 byte %10001 byte %00001 byte %00010 byte %00100 byte %01000 byte %11111 byte %11111 '3 byte %00010 byte %00100 byte %00010 byte %00001 byte %10001 byte %01110 byte %00100 '4 byte %01100 byte %00100 byte %00100 byte %00100 byte %00100 byte %01110 font8x10 byte 8,10,0,0 byte %01110 '0 byte %10001 byte %10011 byte %10101 byte %11001 byte %10001 byte %01110 byte %00100 '1 byte %01100 byte %00100 byte %00100 byte %00100 byte %00100 byte %01110 byte %01110 '2 byte %10001 byte %00001 byte %00010 byte %00100 byte %01000 byte %11111 byte %11111 '3 byte %00010 byte %00100 byte %00010 byte %00001 byte %10001 byte %01110 ' ' more to do ' ' vecdef word $4000+$2000/3*0 'triangle word 50 word $8000+$2000/3*1+1 word 50 word $8000+$2000/3*2-1 word 50 word $8000+$2000/3*0 word 50 word 0 vecdef2 word $4000+$2000/12*0 'star word 50 word $8000+$2000/12*1 word 20 word $8000+$2000/12*2 word 50 word $8000+$2000/12*3 word 20 word $8000+$2000/12*4 word 50 word $8000+$2000/12*5 word 20 word $8000+$2000/12*6 word 50 word $8000+$2000/12*7 word 20 word $8000+$2000/12*8 word 50 word $8000+$2000/12*9 word 20 word $8000+$2000/12*10 word 50 word $8000+$2000/12*11 word 20 word $8000+$2000/12*0 word 50 word 0 pixdef word 'crosshair byte 2,7,3,3 word %%00333000,%%00000000 word %%03030300,%%00000000 word %%30030030,%%00000000 word %%33333330,%%00000000 word %%30030030,%%03000000 word %%03030300,%%33300000 word %%00333000,%%03000000 pixdef2 word 'dog byte 1,4,0,3 word %%30000033 word %%03333333 word %%03333300 word %%03000300 pchip byte "Propeller",0 'text PUB ms(Period) '1 mS if period waitcnt(_1mS * Period + cnt) DAT ' ' The LCD is placed into graphics mode and updated continuously from the buffer so that ' it behaves similar to any refreshed display such as a TV or VGA ' The buffer size is 1K mapped from start to end over to top left to right, top to bottom on the LCD ' The msb of a byte is left-most. org ST7920 andn outa,_load andn outa,_sck or dira,_load or dira,_sck or dira,_sdo mov udly,cnt add udly,_udly mov r0,#$01 call #txcmdl mov r0,#$06 call #txcmd mov r0,#$0C call #txcmd mov r0,#$18 call #txcmd mov r0,#$24 call #txcmd mov r0,#$22 call #txcmd mov r0,#$02 call #txcmd mov r0,#$36 call #txcmd ' mov atr,par ' add atr,lcdsz lcd_loop mov bufptr,par ' set start address mov yptr,#0 lcd_loopy mov r0,yptr ' read line and r0,#$1F or r0,#$80 ' Y addr call #txcmd mov r0,#$80 ' X = 0 (start of line) cmp yptr,#32 wc ' in bottom half of display? if_nc or r0,#$08 ' offset X to access bottom half with mirrored Y call #txcmd mov xcnt,#16 ' 16 bytes per line lcd_loopx rdbyte r0,bufptr rev r0,#24 call #txdat add bufptr,#1 djnz xcnt,#lcd_loopx add yptr,#1 cmp yptr,#64 wz if_ne jmp #lcd_loopy ' next line rdbyte r0,atrptr or r0,#2 wrbyte r0,atrptr { wloop rdbyte r0,atrptr test r0,#1 wz if_nz jmp #wloop } jmp #lcd_loop txdat mov rssel,rsmask rdbyte r1,atrptr test r1,#$10 wz if_nz xor r0,#$ff call #transmit mov udly,cnt add udly,lcddly waitcnt udly,#0 txdat_ret ret txcmd mov rssel,#0 call #transmit mov udly,cnt add udly,lcddly waitcnt udly,#0 txcmd_ret ret txcmdl mov rssel,#0 call #transmit mov udly,cnt add udly,ms1 add udly,ms1 waitcnt udly,#0 txcmdl_ret ret transmit ' transmit r0 as 25 bits mov r1,r0 and r1,umask ' d7d6d5d4 rol r1,#8 rol r0,#4 and r0,#$f0 ' d3..d0 or r0,r1 or r0,synch or r0,rssel or outa,_load rol r0,#8 ' prep data shift from bit23 mov r2,#24 :txloop rol r0,#1 wc muxc outa,_sdo nop nop or outa,_sck nop nop andn outa,_sck nop nop djnz r2,#:txloop andn outa,_load transmit_ret ret _load long 0 '|<scs _sdo long |<sdo _sck long |<sck msb long $80000000 synch long %11111000_00000000_00000000 _udly long 80000 umask long %1011110000 rsmask long %00000010_00000000_00000000 ms1 long 80000 ms10 long 800000 lcddly long 80*(72-15) lcdsz long 1024 atrptr long atr 'atr res 1 r0 res 1 r1 res 1 r2 res 1 r3 res 1 r4 res 1 r5 res 1 yptr res 1 xcnt res 1 bufptr res 1 rssel res 1 udly res 1