my uC

[mstechca]

This is very interesting.

I have made a circuit that allows me to write the same data in the flash memory of the at89c2051 from start to finish.

See the circuit below.

Pins 3.3 through 3.7 are set in flash write mode. I didn't show it in the diagram nor did I show any power supply because that is the simple part.

This circuit takes Amtel's step-by-step procedure of programming the flash.

The circuit performs the procedure as follows with 8uS delay between each step:

1. Increment counter. (make XTAL1 high)
2. Increment counter again. (XTAL is low, and P3.2 is high)
3. Reset counter to 0. (P3.2 is low)

This goes over and over again endlessly.

If there is a disadvantage, I think the only one is that the first byte isn't changed. That I can do manually. In fact, I'll make it a no operation byte
:lol:

Now I want to allow my computer to inject data into this microcontroller in a timely fashion. I don't want to see any data missing.

As far as the parallel port (on my computer) is concerned, when the computer sends data to the PC port, is the output of the PC port constant until the computer sends new data?

I want to use my own clock rather than the strobe on the parallel port because I want each and every chip to work 100%.

Can I get away with making the parallel port's busy signal high until the microcontroller wants the next piece of data? or am I going to lose characters?

and what is the best way to modify my circuit to make it work with the parallel port?

I'm sorry I'm asking so much on this, but I want to see this microcontroller work.

 

[Jay.slovak]

This is very interesting.

I have made a circuit that allows me to write the same data in the flash memory of the at89c2051 from start to finish.

See the circuit below.

Pins 3.3 through 3.7 are set in flash write mode. I didn't show it in the diagram nor did I show any power supply because that is the simple part.

This circuit takes Amtel's step-by-step procedure of programming the flash.

The circuit performs the procedure as follows with 8uS delay between each step:

1. Increment counter. (make XTAL1 high)
2. Increment counter again. (XTAL is low, and P3.2 is high)
3. Reset counter to 0. (P3.2 is low)

This goes over and over again endlessly.

If there is a disadvantage, I think the only one is that the first byte isn't changed. That I can do manually. In fact, I'll make it a no operation byte
:lol:

Now I want to allow my computer to inject data into this microcontroller in a timely fashion. I don't want to see any data missing.

As far as the parallel port (on my computer) is concerned, when the computer sends data to the PC port, is the output of the PC port constant until the computer sends new data?

I want to use my own clock rather than the strobe on the parallel port because I want each and every chip to work 100%.

Can I get away with making the parallel port's busy signal high until the microcontroller wants the next piece of data? or am I going to lose characters?

and what is the best way to modify my circuit to make it work with the parallel port?

I'm sorry I'm asking so much on this, but I want to see this microcontroller work.

Why don't you just make a programmer with schemes from Internet? It's cheaper, takes less time and it is proved to work. This will just bring you problems...

 

[mstechca]

not all programmers work.

Experience happens to be the best learning tool

 

[Jay.slovak]

not all programmers work.

Experience happens to be the best learning tool

Building your own programmer will be hard, beacuse there are 3 types of problems you will face:

1. SW problems of your own programming Software
2. HW problems of your own custom design
3. Unfunctional program to be written to the MCU

If one of these points fails, it will be very hard to find the problem.

 

[mstechca]

Building your own programmer will be hard, beacuse there are 3 types of problems you will face:
1. SW problems of your own programming Software
2. HW problems of your own custom design
3. Unfunctional program to be written to the MCU
If one of these points fails, it will be very hard to find the problem.

#1, and #3 are unimportant right now. It is just the matter of feeding the correct data from the computer to the uC. Once that is accomplished, then I can worry about #1 and #3.