12f675 and midi!

[mischl]

hi

cool project!

i did the same with an 16f876a once, here the most important settings :

DEFINE        OSC           20            ' oscillator speed
define        HSER_TXSTA    20h           ' enable transmit register
define        HSER_BAUD     31250         ' midi baud rate

hserout [$90,$45,$40] ' send a midi comand. noteon ch 1. middle A. middle velocity

this commands and defines are the same on a 12f675

eventually it would be possible to work with the debug command on the 12f675 and you could use the internal oscillator. must be tried. the debug command is the most fastest of the serial commands.
take a look at the pbp manual for setup the right debug settings.

I used this hardware setup

cheers

[Alaskanphoenix]

thank you mischl!

But the hserout command "Send one or more Items to the hardware serial port" and the 12f675 hasn't one!

I used this SerOut2 PORTB.3,12,[$B0,0,control] with a 16f84a and it's ok,but with 12f675 it doesn't work!

Any idea?

[Ingvar]

GPIO.3 is INPUT ONLY. Use a different pin and please read the datasheet. You probably need to disable AD and comparator aswell.

[Alaskanphoenix]

I used gpio.2 as output to send midi messages and i must use the gpio.0 and gpio.1 as ad inputs with pots!

I'm a beginner in pic programming,so please explain me how to configure these pins!

Thanks a lot

[mischl]

uuups. sorry, you are right, there is no uart at the 12f675 ;-)

look at the manual under SEROUT2 for calculating baud rate. 31250 baud needs a 20 mhz crystal.

for analog in : some sample program with a 12F675 look at TESTX4.BAS

[Alaskanphoenix]

I tried to use an external 20 mhz xtal with the serout2 but nothing!
Then i used the debug command with the internal xtal and finally some message appears but wrong,probably it can't reach 31250 baud! how can i disable the internal and use the external xtal?

[mischl]

please post your code si we can take a look

you can define the osc as usual, don't write any : @ DEVICE pic12F675, INTRC_OSC ' activates internal osc

how looks your serout2 command?

[Ingvar]

You set the use of an exernal oscillator in your programmer software, in your case you should look for HS oscillator. To make GP0 and 1 analog inputs, GP2 digital output and ADconverter 10bit, you should probably(never used the 12F675) use ....

TRISIO = %00000011
ANSEL = %00110011
ADCON0 = %10000001

ADvalue VAR WORD

ADCIN 0,ADvalue ' Read channel 0
ADCIN 1,ADvalue ' Read channel 1