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mc68hc11 CME11E9-EVBU board

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ProFPGA

Banned
I am trying to blink leds connected on portc in hc11 , it is in expanded mode .
here's the code :

LDAA #$FF
STAA DDRC ; Making Port C Output
LDAB #$00 ; Pulling all pins down
STAB PortC
** a delay
LDAB #$FF
STAB PortC

but nothing happens , i have measured the voltage level it never goes up or down 2.45Vdc .

any clues ?????
 

futz

Active Member
I am trying to blink leds connected on portc in hc11 , it is in expanded mode .
here's the code :

LDAA #$FF
STAA DDRC ; Making Port C Output
LDAB #$00 ; Pulling all pins down
STAB PortC
** a delay
LDAB #$FF
STAB PortC

but nothing happens , i have measured the voltage level it never goes up or down 2.45Vdc .

any clues ?????
Don't forget a second delay after setting PortC high, like this:
Code:
       LDAA #$FF
       STAA DDRC ; Making Port C Output
       LDAB #$00 ; Pulling all pins down
       STAB PortC
** a delay
       LDAB #$FF
       STAB PortC
[COLOR="Red"]**another delay[/COLOR]
Without the second delay the LED is on for such a short time you can't see it, much less measure it with a meter.

Also, your code doesn't show it so I'll mention it in case you don't know - a label at the top of that bit of code and a branch to the top of it so it loops. Like this (excuse my ultra-rusty HC11 coding and adjust to suit):
Code:
loop   LDAA #$FF
       STAA DDRC ; Making Port C Output
       LDAB #$00 ; Pulling all pins down
       STAB PortC
** a delay
       LDAB #$FF
       STAB PortC
[COLOR="Red"]**another delay[/COLOR]
       bra   loop
 
Last edited:

ProFPGA

Banned
Don't forget a second delay after setting PortC high, like this:
Code:
       LDAA #$FF
       STAA DDRC ; Making Port C Output
       LDAB #$00 ; Pulling all pins down
       STAB PortC
** a delay
       LDAB #$FF
       STAB PortC
[COLOR="Red"]**another delay[/COLOR]
Without the second delay the LED is on for such a short time you can't see it, much less measure it with a meter.

Also, your code doesn't show it so I'll mention it in case you don't know - a label at the top of that bit of code and a branch to the top of it so it loops. Like this (excuse my ultra-rusty HC11 coding and adjust to suit):
Code:
loop   LDAA #$FF
       STAA DDRC ; Making Port C Output
       LDAB #$00 ; Pulling all pins down
       STAB PortC
** a delay
       LDAB #$FF
       STAB PortC
[COLOR="Red"]**another delay[/COLOR]
       bra   loop
Well this was a part of the code that i copied .
I have solved part of the problem , i.e in expanded mode i can not use port c , as i am trying to use here .

So i switched to port d instead , but i ran into problems there as well .
I tried to write certain values to port d in buffalo i.e

mm 1009 // DDRD

#$3F // To make port d output

mm 1008

#$31

// and then i continued to 2, 3, .... A and F

But strangly only leds after $34 changed and remained unchanged till #38

I also have to use hc11 in expanded mode cuz i have to enable xirq !!!!

they dont show the binary equivalent of all the numbers i tried to write ???

i am confused ???

any help plzzz

:eek:
 
Last edited:

kchriste

New Member
Forum Supporter
they dont show the binary equivalent of all the numbers i tried to write ???
You really need to look at the datasheet for the 68HC11.
Port D is only 6 bits and two of those bits are used for Rx and Tx data for the UART which is the communication path for the Buffalo monitor program.
I also have to use hc11 in expanded mode cuz i have to enable xirq !!!!
I don't see why this would be so. Explain.
 

ProFPGA

Banned
Yes i am aware of that Port D has only 6-bits active , thats why each number has $3 and the binary that i want to display . but still dosent makes sense .

I am using CME11E9-EVBU board , i have tried using xirq in single chip mode and there wasnt any reaction , but i did worked in expanded mode .


????
 

kchriste

New Member
Forum Supporter
Yes i am aware of that Port D has only 6-bits active , thats why each number has $3 and the binary that i want to display . but still dosent makes sense
.
PD0 & PD1 are for the UART which is the communication path for the Buffalo monitor program. PD2 is for the SPI which, if enabled, will dominate the pin.
I am using CME11E9-EVBU board , i have tried using xirq in single chip mode and there wasnt any reaction , but i did worked in expanded mode .
I'm not familiar with the CME11E9-EVBU board. You need to be aware that the interrupt vector table is in a different location if you are in bootstrap mode as opposed to normal mode. It is also possible that the vector can be stored in external EEPROM depending on how your CME11E9-EVBU board is configured.
 

ProFPGA

Banned
i have fixed the problem , it was the start address of my program i.e $2000.
I can now run it in single chip mode and also at address $0100 .

:)
 

barfleur

New Member
i have fixed the problem , it was the start address of my program i.e $2000.
I can now run it in single chip mode and also at address $0100 .

:)
Yes you fixed the problem, good on you, that's the spirit. Now you'll need to investigate why it wasn't working before.

Cheers :)
 
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