Post by thread:16C74

I heard these just went into sample(call MicroChip today). Has anyone gotten ahold of one to play with? I really want to see how well the UART on it works... Also 4K of eprom! 2K is too little on the 64 i think. The 64 can do so much but with only 2K you can exploit only a little of it :( later John _____________________________________________________________________________ John Johnson |If it's not OS/2.|spam_OUTjohnsonjTakeThisOuTutdallas.edu |It's crap! |.....johnsonjKILLspam@spam@ghostwheel.bga.com OOOO SSSS /2222 2222 11 | | O O S / 2 2 1 |"We need breath- |"Bite me." Tom Servo O O SSSS / 2222 2222 1 |-ing room!" | O O S / 2 2 .. 1 | Bill Gates |"I want to decide who lives OOOO SSSS/ 2222 2222 .. 111| |and who dies" Crow T. Robot -----------------------------------------------------------------------------

John M. Johnson <johnsonjKILLspamUTDALLAS.EDU> asks: > Has anyone gotten ahold of one to play with? I just today recieved my PICSTART-16C with a PIC16C74 sample (marked "ENG SMP" and with a date code of 9430. I'll try it out tonight. > Also 4K of eprom! 2K is too little on the 64 i think. > The 64 can do so much but with only 2K you can exploit only a little of > it :( I'd settle for 2K or even 1K. I have yet to run out of EPROM on a 16C71, although one of my projects got close. On the other hand, I'm constantly having to pack my RAM usage, so having more than 36 general purpose file registers is a big win. I also hope they get the 16C63 and 16C73 out soon. Only occasionally do I need more than 20 I/O lines. IMHO, if you need a lot of ROM or a lot of I/O, you probably are better off with a 68HC11 or 8051 derivative. They seem to be more cost effective than the larger PIC parts. While I don't find the PIC to be too hard to program, I usually find the HC11 to be easier (mostly due to the better addressing modes). On one project I found the most effective solution was to use an HC11 for most of the control, and a PIC16C71 for the time-critical portion. Eric

Hi all, Sorry to ask the very basics, but I'm running into a little trouble :( I've connected up a PIC 16C74 on a breadboard, and am feeding in a 4Mhz signal onto pin 13 (the Clk in pin) from a signal generator. I'm applying 5v to pins 11 & 32, with 0v on 12 & 31 As far as I can tell at the moment, that should mean a program I put onto the pic should run? So I wrote a small program (very small :) to turn port D into an output and blat bits out of it, incrementing. . such as this org 0 goto start org 50 start movlw B'00000000' movwf TRISD ; Setup port D for all outputs clrf PORTD ; Blank it bsf STATUS, RP0 main_loop addlw 1 ; add 1 to W movwf PORTD ; copy W to port D goto main_loop end This appears to toggle between 8 & 9 for some reason under MPSIM Am I missing something? Does anyone have any sample 16c74 code out there I could peruse :) Cheers, Glyn D. -- Glyn D / http://www.cs.man.ac.uk/~daviess / Computer Science 3rd year ------------------------------------------------------------------------ "Whom computers must destroy, they must first drive mad." -- fortune "What if everyone felt like that?" -- Catch 22 ------------------------------------------------------------------------

> I've connected up a PIC 16C74 on a breadboard, and am feeding in a > 4Mhz signal onto pin 13 (the Clk in pin) from a signal generator. > > I'm applying 5v to pins 11 & 32, with 0v on 12 & 31 What about /MCLR? If you don't pull it up, the chip will stay in reset. What oscillator mode are you using? > So I wrote a small program (very small :) to turn port D into an output > and blat bits out of it, incrementing. . such as this You're using the outputs "open-collector"? It looks like you're writing to the TRIS registers? [bcf RP0 to avoid that methinks]

Glyn: Set STATUS, RP0 _Before_ writing to TRISD and clear STATUS, RP0 _After_. The code for any of the PIC 16CXX's (not 5X's) applies directly, as far as style and method. The '74 just has more stuff. The '5X code applies with some minor mods. Get the embedded control handbook and read it and the data book. Brian

> > > I've connected up a PIC 16C74 on a breadboard, and am feeding in a > > 4Mhz signal onto pin 13 (the Clk in pin) from a signal generator. > > > > I'm applying 5v to pins 11 & 32, with 0v on 12 & 31 > > What about /MCLR? If you don't pull it up, the chip will stay in reset. > What oscillator mode are you using? I've tried with it pulled up, seems no go still :( The oscillator is in XT mode, the signal is coming from a function generator > > > So I wrote a small program (very small :) to turn port D into an output > > and blat bits out of it, incrementing. . such as this > > You're using the outputs "open-collector"? It looks like you're writing to > the TRIS registers? [bcf RP0 to avoid that methinks] > What will a bcf RP0 do then? Thanks, Glyn -- Glyn D / http://www.cs.man.ac.uk/~daviess / Computer Science 3rd year ------------------------------------------------------------------------ "Whom computers must destroy, they must first drive mad." -- fortune "What if everyone felt like that?" -- Catch 22 ------------------------------------------------------------------------

Brad Pousland <.....bpouslanKILLspam.....MOLE.UVM.EDU> wrote: > Is the 16c74 CERDIP windowed package UV erasable or OTP? If it's windowed, it's a fair bet it's UV erasable! -- Clyde Smith-Stubbs | HI-TECH Software, | Voice: +61 7 3300 5011 EraseMEclydespam_OUTTakeThisOuThitech.com.au | P.O. Box 103, Alderley, | Fax: +61 7 3300 5246 http://www.hitech.com.au | QLD, 4051, AUSTRALIA. | BBS: +61 7 3300 5235 --------------------------------------------------------------------------- For info on the World's best C cross compilers for embedded systems, point your WWW browser at http://www.hitech.com.au, or email infospam_OUThitech.com.au

Brad Pousland wrote: > Is the 16c74 CERDIP windowed package UV erasable or OTP? It is windowed, so it is erasable! Wolfram -- +-----------------------------------------------+ ! Wolfram Liebchen, @spam@liebchenKILLspamipserv.ffo.fgan.de ! ! Forschungsinstitut fuer Optik ! +-----------------------------------------------+

> Is the 16c74 CERDIP windowed package UV erasable or OTP? No, it is solar powered! Erik --------------------------------------------------------- Professional Audio Center Phone: (+31) (0)40 251 04 84 fax: (+31) (0)40 257 04 82 EMail: KILLspamErikKILLspameela.nl Erik Nieuwlands