at89s51 Programmer using PIC Microcontroller

[sukumar]

pic programmer

Hi All,

I am Using PIC16f877a's SPI Protocol to program the 8051 IC.
My design is to Program the 89s51 one by one ie..Single byte at a time.
I will get the Address, Opcode from Serial Port(No intel Hex Format) and Programming the 89s51.

I Programmed the IC successfully and Tested it.

Here the Problem i cannot write a same location second time.
For Example:
I have written 0x0046--0xaa

If i Write the same location Second Time 0x0046---0x32.

The Location 0x0046 changed to 0x00...( 0x32 not written).

Why?

 

[nandhu015]

First you have to erase the content (make all the locations 0xff)

Nandhu

 

[sukumar]

Hi,

Is there any method to erase a Particular memory location?
Erasing all the contents will erase everything
but i need to edit some portion of a large program by modifying few memory locations only.
remaining content should be retained.
That particular memory location editing is not working. thats is my problem

 

[wek]

No, you can erase only the whole chip.

The only way to modify a part of the content is to read the whole content into a temporary storage (I'd use an external serial eeprom e.g. 24Cxx, if there is not enough internal storage onchip of the PIC); perform the erase, and then write back the modified content.

JW

 

[sukumar]

I already Included SEEPROM in My Board.

Then I thought you people will have different Idea.

Okay. I will Try With Serial Memory. Thanks a Lot for all.

Just Suggest any other 16Fxx IC compatible with 16f877a with more EEPROM?

 

[Medtronic]

Dear My Friend sukumar

Can you please shar your sucess with us,share your programmer schematic and firmware wiyh my pleasure

Best Regards

 

[anandpv2009]

yes. I am also trying to make one like that.