making 89s51/52 89s8253 /8253 programmer

[tushki7]

I've used the serial programmer with master but the same message pops showing "trying to connect by COM1".
I dont see a bug in the circuit .

What cable you are using for connection between your pc and circuit?

 

[sunlabs]

Using serial to USB converter. Starting to think if this is the bug , but when i short the serial pins it echoes back in the hyperterminal .

But when i short the txd and rxd pins in the board it doesn't echo back . What could be the problem?

 

[tushki7]

But when i short the txd and rxd pins in the board it doesn't echo back . What could be the problem?

Check your circuit again .. after connecting usb to serial, check which com port is it using:
right click on My Computer and click properties go to device manager and check com port number in mine its com4 as shown:


This is your port number(as in mine com4). you have to use this not com1(as com1 is by default).. If your usb to serial shows com1 then only you can use it.
What programmer you are using? what software?

 

[sunlabs]

Its called EPR labs serial debugger and it programs at89s52 using at89c2051 .
**broken link removed**

 

[casamiro]

Buddy if you have enough time so try to make yourself no doubt you will learn to much I grantee you
but if you don't have just stop Googling and just by a usb or serial programmer it will really save your time and money and consume your time to make and test the programs rather then built a programmer.