Maximum Operation Frequency? - Electronic Circuits Projects Diagrams Free

Andy1845c · 15th February 2007, 12:21 AM

I'm looking at the datasheet for the PIC16f54. it says "Maximum Operation Frequency - 20MHz" - does that mean I could use a 12MHz crystal to get somthing up and running? I'm trying to sub the 16f54 for the 16f84a in the inchworm "Hello World" jumpstart. He's uses a 4MHz crystal, but I don't have one (that I have found so far..) But I do have what I am pretty sure is a 12MHz. How critical are the decoupling cap values?

Sceadwian · 15th February 2007, 03:02 AM

Not sure what the Hello World program uses for it's output, but if it's an RS232 out then you'll have to recalculate the baud rate for the new crystal value. Basically three times the 4mhz value.

**Nigel Goodwin** · 15th February 2007, 07:41 AM

Quote:

Originally Posted by Andy1845c

I'm looking at the datasheet for the PIC16f54. it says "Maximum Operation Frequency - 20MHz" - does that mean I could use a 12MHz crystal to get somthing up and running? I'm trying to sub the 16f54 for the 16f84a in the inchworm "Hello World" jumpstart. He's uses a 4MHz crystal, but I don't have one (that I have found so far..) But I do have what I am pretty sure is a 12MHz. How critical are the decoupling cap values?

PIC's work on anything from DC to their maximum rating (and usually above it as well), for a 12MHz crystal select HS in the config fuses.

As suggested you will have to recalculate anything that's time specific, and the tuning capacitors aren't at all critical - I just use anything to hand between 10pF and 33pF.

Andy1845c · 15th February 2007, 02:28 PM

Cool! Thanks guys. Now as soon as my USB/Serial cable comes in the mail I should finally be able to flash my first LED via a PIC!

blueroomelectronics · 15th February 2007, 08:08 PM

Just make sure you select HS as the for the oscillator option. A config value of 0x0FFE should work for the 16F54

Code:

_CONFIG 0x0FFE

It's also possible to use simply a resistor and a capactor as the clock. Thats what the RC clock is for. PICLIST describes the RC clock here.
http://www.piclist.com/techref/microchip/osc.htm

I like the old 54, it's a really simple PIC and really old now. Thankfully most modern PICs now have an internal osc option.

Andy1845c · 15th February 2007, 08:19 PM

Quote:

Originally Posted by blueroomelectronics

Thankfully most modern PICs now have an internal osc option.

lol, yeah, now I have learned that

I wish I would have know when I ordered some PICs to play with.

My serial cable came in the mail today, so, with any luck, i'll have somthing up and running tonight.

blueroomelectronics · 16th February 2007, 01:39 AM

If you can get your hands on a 16F88 you can play with the debugger, it is a complex chip compared with the 16F54.

Andy1845c · 16th February 2007, 02:56 AM

Well,..... its not working

I'm trying to run William's Hello World program, but I can't seem to connect to the inchworm.
This is what I get

Connecting to MPLAB ICD 2
ICD0021: Unable to connect with MPLAB ICD 2
MPLAB ICD 2 Ready

I am using a USB to Serial RS232/DB9 9-PIN Converter Cable.
I have COM PORT set to COM 1 - is this right? What is COM 1? I have 4 USB ports on my computer, are they all the same or will only a certin one work?

I hope I'm just making a simple mistake on somthing and I didn't solder somthing in wrong on the inchworm.

Anyone have any ideas? ........

blueroomelectronics · 16th February 2007, 03:16 AM

Quote:

Originally Posted by Andy1845c

Well,..... its not working

I'm trying to run William's Hello World program, but I can't seem to connect to the inchworm.
This is what I get

Connecting to MPLAB ICD 2
ICD0021: Unable to connect with MPLAB ICD 2
MPLAB ICD 2 Ready

I am using a USB to Serial RS232/DB9 9-PIN Converter Cable.
I have COM PORT set to COM 1 - is this right? What is COM 1? I have 4 USB ports on my computer, are they all the same or will only a certin one work?

I hope I'm just making a simple mistake on somthing and I didn't solder somthing in wrong on the inchworm.

Anyone have any ideas? ........

Did you download the OS to the inchworm? Also make sure the FIFO buffers are off.

Andy1845c · 16th February 2007, 03:28 AM

I have it set to auto download the correct OS. Is there a way to make sure its working/manually do it?

I did turn off FIFO buffer.

Any other ideas?

Andy1845c · 16th February 2007, 03:46 AM

It seems like no matter what I try it can't connect....

ICD0021: Unable to connect with MPLAB ICD

When I try to select Download ICD2 Operating System from the Programer menu, the only file that shows up is ICD07010400.hex, and when I try it, it can't connect and fails

blueroomelectronics · 16th February 2007, 04:02 AM

What brand of USB to RS232 adapter is it? Can you tell if it uses the PL2303 chipset? (If so look on my download section for a working PL2303 driver)

Andy1845c · 16th February 2007, 04:35 AM

I can't find any info on the chipset. I can't get any drivers to install either...... After downloading the one off your site, should the windows hardware wizard find it and install it? I can't get it to, and can't get it to manually install either

Nothing is going right tonight.....

I appreciate your help though! Inchworm tech suppoert is top notch

blueroomelectronics · 16th February 2007, 09:01 PM

There is usually a driver cd with the adapter. What brand is it? Right click on my computer / properties / hardware look for the comm adapter and it will tell you the chipset.

The PL2303 is only for a PL2303 USB / Serial bridge.

Hero999 · 16th February 2007, 10:11 PM

A hello world program for a PIC?

Wouldn't that be quite complicated, as you'd need a dot matrix LED display?

I would think you probably mean the PIC equivalent to a hello world program, i.e. a simple tes program to show it's working. I suppose this would be something simple like flashing an LED.

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15th February 2007, 12:21 AM	(permalink)
Andy1845c	Maximum Operation Frequency? I'm looking at the datasheet for the PIC16f54. it says "Maximum Operation Frequency - 20MHz" - does that mean I could use a 12MHz crystal to get somthing up and running? I'm trying to sub the 16f54 for the 16f84a in the inchworm "Hello World" jumpstart. He's uses a 4MHz crystal, but I don't have one (that I have found so far..) But I do have what I am pretty sure is a 12MHz. How critical are the decoupling cap values?

15th February 2007, 03:02 AM	(permalink)
Sceadwian	Not sure what the Hello World program uses for it's output, but if it's an RS232 out then you'll have to recalculate the baud rate for the new crystal value. Basically three times the 4mhz value. __________________ "Because I be what I be. I would tell you what you want to know if I could, mum, but I be a cat, and no cat anywhere ever gave anyone a straight answer, har har."

15th February 2007, 02:28 PM	(permalink)
Andy1845c	Cool! Thanks guys. Now as soon as my USB/Serial cable comes in the mail I should finally be able to flash my first LED via a PIC!

15th February 2007, 08:08 PM	(permalink)
blueroomelectronics	Just make sure you select HS as the for the oscillator option. A config value of 0x0FFE should work for the 16F54 Code: _CONFIG 0x0FFE It's also possible to use simply a resistor and a capactor as the clock. Thats what the RC clock is for. PICLIST describes the RC clock here. http://www.piclist.com/techref/microchip/osc.htm I like the old 54, it's a really simple PIC and really old now. Thankfully most modern PICs now have an internal osc option. __________________ Bill Smart Kits build Smart People http://www.blueroomelectronics.com

16th February 2007, 01:39 AM	(permalink)
blueroomelectronics	If you can get your hands on a 16F88 you can play with the debugger, it is a complex chip compared with the 16F54. __________________ Bill Smart Kits build Smart People http://www.blueroomelectronics.com

16th February 2007, 02:56 AM	(permalink)
Andy1845c	Well,..... its not working I'm trying to run William's Hello World program, but I can't seem to connect to the inchworm. This is what I get Connecting to MPLAB ICD 2 ICD0021: Unable to connect with MPLAB ICD 2 MPLAB ICD 2 Ready I am using a USB to Serial RS232/DB9 9-PIN Converter Cable. I have COM PORT set to COM 1 - is this right? What is COM 1? I have 4 USB ports on my computer, are they all the same or will only a certin one work? I hope I'm just making a simple mistake on somthing and I didn't solder somthing in wrong on the inchworm. Anyone have any ideas? ........

16th February 2007, 03:28 AM	(permalink)
Andy1845c	I have it set to auto download the correct OS. Is there a way to make sure its working/manually do it? I did turn off FIFO buffer. Any other ideas?

16th February 2007, 03:46 AM	(permalink)
Andy1845c	It seems like no matter what I try it can't connect.... ICD0021: Unable to connect with MPLAB ICD When I try to select Download ICD2 Operating System from the Programer menu, the only file that shows up is ICD07010400.hex, and when I try it, it can't connect and fails

16th February 2007, 04:02 AM	(permalink)
blueroomelectronics	What brand of USB to RS232 adapter is it? Can you tell if it uses the PL2303 chipset? (If so look on my download section for a working PL2303 driver) __________________ Bill Smart Kits build Smart People http://www.blueroomelectronics.com

16th February 2007, 04:35 AM	(permalink)
Andy1845c	I can't find any info on the chipset. I can't get any drivers to install either...... After downloading the one off your site, should the windows hardware wizard find it and install it? I can't get it to, and can't get it to manually install either Nothing is going right tonight..... I appreciate your help though! Inchworm tech suppoert is top notch

16th February 2007, 09:01 PM	(permalink)
blueroomelectronics	There is usually a driver cd with the adapter. What brand is it? Right click on my computer / properties / hardware look for the comm adapter and it will tell you the chipset. The PL2303 is only for a PL2303 USB / Serial bridge. __________________ Bill Smart Kits build Smart People http://www.blueroomelectronics.com

16th February 2007, 10:11 PM	(permalink)
Hero999	A hello world program for a PIC? Wouldn't that be quite complicated, as you'd need a dot matrix LED display? I would think you probably mean the PIC equivalent to a hello world program, i.e. a simple tes program to show it's working. I suppose this would be something simple like flashing an LED. __________________ I also post at the following sites: http://www.stop-microsoft.org http://www.heated-debates.com Screen name: Aloone_Jonez And http://www.silicontronics.com, same screen name as here.