MCLR with PIC12F675

cLuciano · Joined: 27 Dec 2006 Posts: 8

MPlab returns the following error:

ICDWarn0043: MPLAB ICD 2 cannot debug the selected device while it is configured for internal MCLR. Would you like to select external MCLR?
ICD0200: Operation Aborted (Warning 42).
ICD0275: Programming failed.
MPLAB ICD 2 Ready

The progeram is like follows:

#include "12F675.h"
#define PIC_CLK 4000000
#device ADC=10
#use delay (clock=PIC_CLK)
#use fast_io(a)
#FUSES INTRC_IO,MCLR,NOWDT

In the 'Configuration Bits' window the 'Master Clear Enable' always is 'Internal'

ckielstra · Joined: 18 Mar 2004 Posts: 3680 Location: The Netherlands

What is your compiler version? (See top of the *.lst file)

cLuciano · Joined: 27 Dec 2006 Posts: 8

3.242

Humberto · Posted: Thu Feb 08, 2007 2:02 pm

From the Microchip 12F675 Datasheet:

Page 54
Configuration bits:
bit 5 MCLRE: GP3/MCLR pin function select(5)
1 = GP3/MCLR pin function is MCLR
0 = GP3/MCLR pin function is digital I/O, MCLR internally tied to VDD

Page 58
"An internal MCLR option is enabled by setting the
MCLRE bit in the configuration word.
When enabled, MCLR is internally tied to VDD.
No internal pull-up option is available for the MCLR pin."

Am i wrong or there is a mistake in the bit 5 of the Configuration Word definition?

Anyway, did you try
#FUSES INTRC_IO,NOMCLR,NOWDT

Humberto

adrian · Joined: 08 Sep 2003 Posts: 92 Location: Glasgow, UK

Firstly, the 12F675 is an 8 pin device and you cannot debug this device - you need to use the header board with the special 12F675-ICD.

Secondly there is a limitation in that you cannot programme the device with the ICD2 when it is configured for internal clock and internal MCLR.

The programming limitation does not apply to the PICkit 1 or 2, which is what I used to get round the internal clock and internal MCLR.