Hi all,

is there a particular procedure for causing a dsPIC reset with
a switch or IC ? I've got a dsPIC circuit with a tact switch on
/MCLR that doesn't seem to do a proper hardware reset. At
some point I'd like to add a reset from another device, and a
tact switch seemed a quick test

/MCLR has an RC on it (10k to Vcc, 47n to Vss, 100R input
resistance). So it's normally held high and grounded through the
tact switch. I've done this with just about very other PIC and
they do reset properly.

On this circuit, the LCD attached doesn't re-initialise. I can tell
because the power-up display is in two stages and s/w doesn't
seem to reach that point. No activity is apparent on the dsPIC
after the switch is pressed, apart from all the I/O I'm monitoring
going high. Pressing the tact switch 'seems' to do little or nothing.

On any other PIC I would expect to see the LCD re-boot with
the power-up display message

Very little mention is made in the datasheet of the /MCLR pin,
which is its only function. I can't find any reference to it in the
..inc file (eg on other PICs you can turn MCLR on/off)

Right at the start of the project is

         .include "P33FJ64GP802.inc"

  .global __reset             ;program entry point
  .global __U1RXInterrupt     ;receiver ISR
  .global __T1Interrupt       ;Timer 1 ISR

and power-up successfully goes through this

           .text

          __reset:

init:      clr     LATA
           clr     LATB
etc

Is there something else I need to add ?

TIA

Joe


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