89SXX series Microcontroller SPI Program loader

hello all,

i have made 89sXX programmer.
from ::

**broken link removed**

Click to expand...

but due to inavailibity of 74HCT541 in our town i have used 74HC244.
i have checked all the possible way from my side
but still its not running..

can any one help me...??

Thanks to all in advance...!!!

Hai

541 is not pin compitable with 244
Have you checked it out?

If it is correct then try 74HCT244

Regards
Nandhu

hi nandhu,..

i have checked both the datasheet.
i found one noticable difference is its logic symbol..
i am uploading here.
please check and tell me will it make any difference in operation..??

if yes then how can i make them to do same operation.

thanks for the replying.

Not much as you feel.

There are two individual controls in 244 while a 541 has a single control.

in the circuit i think it makes no difference if you short 2 individual controls in 244.

Check the circuit twice. Check the port (just check it with a printer).

come up with the results

Nandhu

Hai H_D_R,
while the connections 1&19 are low, you may have to select the gates for keeping in view of the input and output pins are different gates.

Once you take care of this situation,( i mean you can't wire pin to pin with 541)you must succeed, unless some other mistake is committed . That would be revealed if you can put up the schematic as to how you wired it..

BTW, please ensure that pins 2 and 12 of DB25 connector are looped as suggested by asimkhan on the schematics at the foot note.
Sarma

Hello mvs_sharma,

Thanks for replying..

while the connections 1&19 are low, you may have to select the gates for keeping in view of the input and output pins are different gates.

Click to expand...

I agree with you but according to me it will make difference because in 541 we are using bubbled nand gate while in 244 we are using two bubbled not gate(Inverter).
So, how to make them able for same outputs.???

Once you take care of this situation,( i mean you can't wire pin to pin with 541)you must succeed, unless some other mistake is committed .

Click to expand...

Yes, I have checked by my site and as per circuit is drawn but still if you feel to notice any point then i will be thankful to you.

BTW, please ensure that pins 2 and 12 of DB25 connector are looped as suggested by asimkhan on the schematics at the foot note.

Click to expand...

yes i have done that...

That would be revealed if you can put up the schematic as to how you wired it..

Click to expand...

Here is my SPI programmer circuit. As you have asked for uploading.

All opinion or experience on this problem will be appreciated..

Thank you

That is what I feared. If you wired as if 541 and inserted 244 it would not work.Without changing the gate s to suite pin out of 244 you can't use 244 in a wiring done for 541.
Please observe carefully the input and output pins are not the same for some pins.

the modified schematic attached for ready reference.

Sarma

Hi,
You should have shown the connections you made for 244. Just note the major difference of I/O pin reversals in 244 compared to 541, Eg., pins 3 and 17, have you made corrections in your circuit to take care of such differences?
Other points to be noted are:
1. Put two caps 20 to 30 pfs, on either ends of the crystal.
2. May be you can reduce the resistor value of 1K on the clock line to 100 omhs and try, some times these values and cable length are also critical for such programmers.

3.Check if the software is compatible with the OS you are running under?
- Does the parallel port output bits change states when you run the software? Is the power LED glowing?, It may still glow since on booting, this may be the initial state. So, check the state change of any one of the other pins used in the program to see if software is getting control.
- You may have to set the parallel port to Standard Parallel Port in the CMOS set up for the software to get control.
- When you run the PC software, are you getting the programming screen ?

Regards,
Laktronics

mvs sarma said:

That is what I feared. If you wired as if 541 and inserted 244 it would not work.Without changing the gate s to suite pin out of 244 you can't use 244 in a wiring done for 541.
Please observe carefully the input and output pins are not the same for some pins.

the modified schematic attached for ready reference.

Sarma

Click to expand...

THANK YOU SIR, FOR SENDING THIS SCHEMATIC..
LET ME CHECK THE CONNECTIONS OF THIS CIRUIT WITH MINE..
THEN ONLY I'CAN REPLY WHATEVER WILL BE RESULT...!!:!:

THANK YOU SO MUCH AGAIN....
THANK YOU laktronics YOU TOO...

hello all,

thank you so much for replying me..

i have found some problem but still i have not solved due to little bit busy schedule.

can anyone clear my one doubt...??

in the circuit uploaded by mvs sarma, there is 4.0MHz crystal oscillator is used.
I want to use 11.0592/12.0MHz crystal oscillator then
will it make any difference in Circuit.??
which one is better to use 11.0592MHz or 12.0MHz..??
and will i have to change the value of capacitor if I’ll change crystal oscillator.??
if yes then how to calculate the capacitor value for different crystal oscillator..??

thank you all....

thank you mr. mvs sarma

what crystal you use for programming and the real working crystal clock have no relevance. After programming you replace the crystal to 11.0592 and go ahead

This has been discussed here many times!

and

and

and


Also here:
**broken link removed**

I messed around with that ISP cable for too long!
I realized that it is NOT reliable!

On some PC's it will work (sometimes) while others it would never work. It may read the signature bytes one out of five times but that's it. When i want to program the device, I don't want to be doing hours of debugging!

Why do you need this headache? By the time you pull your hair out trying to figure this out, you could have bought a ready made cable from atmel or another company.

The best and MOST RELIABLE solution is a programmer that uses an on board microcontroller.

Here is one:
**broken link removed**

Source and everything included here. While the description is avr programmer, It does support the 89S series micros. By the time you mess around with the ISP cable, (in the same amount of time & money) you could have built the biprog programmer. Then you will have the most reliable programmer for a long time!

Good Luck