Post by thread:9 bit data to 16F84

> Hi, guys, Newbie in PIC need some help. I want to use 16f84 to clock > in 9 bit of data, LSB first, and then send it to LCD display. Seems > the work register only works with 8 bit data. How could I work this > out? > I'm assuming you are having trouble sending out the data to the LCD display serially... simply put the 9th bit in the carry register and clock the bit out before shifting the other 8 bits. -Vincent Deno

At 13:05 02/19/99 -0500, glam wrote: >Newbie in PIC need some help. I want to use 16f84 to clock >in 9 bit of data, LSB first, and then send it to LCD >display. Seems the work register only works with 8 bit data. >How could I work this out? you could probably use either the carry flag, or, if you use two bytes for intermediate storage anyway, just save it after the first 8 bits. depends on what exactly you do with the 9 bits. ge

Vicent, Thanks for your advise. I am having trouble where to store the 9 bit data. I want to use the first bit, LSB, to drive a LED on/off and the send the rest 8 bits to LCD. But the work register only has 8 bit storage. Gary > >I'm assuming you are having trouble sending out the data to the LCD >display serially... simply put the 9th bit in the carry register and clock >the bit out before shifting the other 8 bits. > >-Vincent Deno >

At 13:05 02/19/99 -0500, glam wrote: >Newbie in PIC need some help. I want to use 16f84 to clock >in 9 bit of data, LSB first, and then send it to LCD >display. Seems the work register only works with 8 bit data. >How could I work this out? First, LCD will only works with 8 bits, so, from the 9 bits it will be receiving, which one will be put away? So you can avoid it right at the reception time. First, last, which one? Wagner.

I want to use the first bit, LSB, to drive a LED and use the rest 8 bits for LCD display. I don't know how to store those 9 bits and then separate the LSB, because the W register only has 8 bits, but the 9 bits of data come in serially. Gary >>I want to use 16f84 to clock in 9 bits of data, LSB first, and then send it to LCD >>display. Seems the work register only works with 8 bit data. >>How could I work this out? > >First, LCD will only works with 8 bits, so, from the 9 bits it >will be receiving, which one will be put away? So you can >avoid it right at the reception time. First, last, which one? > >Wagner.

On Fri, 19 Feb 1999 15:46:17 -0500 glam <spam_OUTglam4seasTakeThisOuTMEDIAONE.NET> writes: >I want to use the first bit, LSB, to drive a LED and use the >rest 8 bits for LCD display. I don't know how to store those >9 bits and then separate the LSB, because the W register >only has 8 bits, but the 9 bits of data come in serially. >Gary One approach is to write the receive routine so it receives the bit that controls the LED first and store it in one place, then receives the 8 bits for the LCD and stores them in another place. That method looks good for a beginner, but is not as clean as receiving all 9 bits at once. It is easy to use data larger than 8 bits on a PIC by storing it in 2 or more "file register" RAM locations. In the case of receiving serial data, do something like: clrc btfsc PORT,bit ;Is the serial input low? setc ;No it's high. ; Now the bit just received is in C. Rotate it into the shift register rrf datahi,f rrf datalo,f After doing this 9 times, the first bit received is in the high bit of datahi, and the last 8 bits received (LSB first) are in datalo. The W register is not too useful for serial reception because it can't be rotated. Use RAM file registers (also 8 bits of course) instead. ___________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com/getjuno.html or call Juno at (800) 654-JUNO [654-5866]

Great! Thank you very much for your advise. Gary. > >It is easy to use data larger than 8 bits on a PIC by storing it in 2 or >more "file register" RAM locations. In the case of receiving serial >data, do something like: > > clrc > btfsc PORT,bit ;Is the serial input low? > setc ;No it's high. >; Now the bit just received is in C. Rotate it into the shift register > rrf datahi,f > rrf datalo,f > >After doing this 9 times, the first bit received is in the high bit of >datahi, and the last 8 bits received (LSB first) are in datalo. > >The W register is not too useful for serial reception because it can't be >rotated. Use RAM file registers (also 8 bits of course) instead. > > > > >___________________________________________________________ ________ >You don't need to buy Internet access to use free Internet e-mail. >Get completely free e-mail from Juno at http://www.juno.com/getjuno.html >or call Juno at (800) 654-JUNO [654-5866]