Can anyone tell me what I need to do to get a 4550 fired up ?
I've got the settings/code below, but no action on the pins

The oscillator is running. Supposed to be 9.8304MHz x 4.
Without any code to measure, can't say whether it is. Let's
just say the OSC pins have 9.8304MHz on them

I've looked at the output on the scope and analyser but nothing
makes sense. For example, this code seems to to do nothing. An
earlier attempt caused all sorts of 'random' noise to come out of
various pins

I had presumed the 4550 could be treated basically like a 452 or
4520, which is what I'm porting a lot of code from, and with which
I've had no problems at all

ConfigBase equ  0x300000            ; base address of config registers

         CONFIG  FOSC= HSPLL_HS

         CONFIG  BOR = OFF, PWRT = ON

         CONFIG  WDT = OFF

         CONFIG  CP0 = OFF, CP1 = OFF, CP2 = OFF, CP3 = OFF

         CONFIG  PBADEN = OFF

         CONFIG  MCLRE = ON

#define  blc     latc,2       ;LCD backlight on/off
#define  lcd_pwr late,0       ;LCD on/off

         org     0x00000      ;start address
         goto    init

         org     0x00020

init     clrf    intcon
         clrf    intcon2
         clrf    intcon3

         mov     b'00000000',trisa
         mov     b'00000000',trisb
         mov     b'00000000',trisc
         mov     b'00000000',trisd
         mov     b'00001000',trise
;                      1            /mclr  10k p/u + reset button

         mov     b'00001111',adcon1
         mov     b'00000111',cmcon
         mov     b'00000000',cvrcon

         clrf    porta
         clrf    portb
         clrf    portc
         clrf    portd
         clrf    porte
         clrf    lata
         clrf    latb
         clrf    latc
         clrf    latd
         clrf    late

         call    ms100        ;short delay
         bsf     lcd_pwr      ;LCD power
         call    ms100
         bsf     blc          ;backlight
         call    ms100

here     bra     here

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