redefine unuse port

[ericgibbs]

you could write a simple software uart routine, for TX data transmission.

 

[blueroomelectronics]

Or move the E & RS pins off PORTB and onto RA6,7
I'm sure it's not important but the internal osc is only 1% at room temperature. Cars get much hotter/colder than that.

 

[scomi]

you could write a simple software uart routine, for TX data transmission.

Yup... I will work on it. But if possible, I really need to switch just the E and RS pins so that I can use the B5 HUART much more easier.

Or move the E & RS pins off PORTB and onto RA6,7
I'm sure it's not important but the internal osc is only 1% at room temperature. Cars get much hotter/colder than that.

Why suddenly involve temperature?
well..that is what i planning to do ...
will report here as soon as i tried it, thanks blue

 

[blueroomelectronics]

Just saying the internal osc will probably drift outside room temperature. A crystal would offer a more accurate timebase.

 

[scomi]

I tried whole day to reconfigure my things and few methods had been used:

A:
I changed the bit mask from 11101111 to 10101111:

Start:
	clrf 	PORTA
	clrf	PORTB
	bsf	STATUS,RP0	; bank 1
	ifdef	__16F88
	movlw	B'10101111'	; PortA directions (16F88) ;previously 11101111 
	movwf	TRISA
	movlw	B'11000001'	; PortB directions (16F88)
	movwf	TRISB
	movlw	B'01100000'	; 4MHz internal osc (16F88)
	movwf	OSCCON

and modify the LCD_RS only to A6 like below:

#DEFINE	PGBTN	PORTB,6	; page button   (S3)
#DEFINE	HDBTN	PORTB,7	; hold button   (S2)
#DEFINE	BLDBTN	PORTA,7	; blades button (S1)

#DEFINE	RPM_IN	PORTB,0	; rpm input

#DEFINE LCD_D7  PORTA,4	; \
#DEFINE	LCD_D6  PORTB,1	; |
#DEFINE LCD_D5  PORTB,2	; | LCD panel
#DEFINE LCD_D4  PORTB,3	; |
#DEFINE LCD_E   PORTB,4	; |
#DEFINE LCD_RS  PORTA,6	; /

and I connect the LCD_RS to A6, leaving B5 not connected to ground, i get a blank on LCD. I found that B5 is interrupt on change pin but A6 do not. Is this affected? Suppose I can change the B5 LCD_RS to A6 (OSC2) right? Sigh..

 

[scomi]

Well..i think i manage to get it. I connected the LCD_RS to A6, then changing the bit pattern for B5 as HIGH. Well..still...need to thanks you guys..

I still have a part to suffer on hardware UART.... hope you guys can keep track of this post. Big thanks...