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[SOLVED] problem of 'resettng isp mode'

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Newbie level 4
Jun 19, 2011
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hello ,i am a btech 2nd year student

1. I am using AT89C51 microcontroller ,
but in the device name , it isn't present ( i modified device field as 89V51RD2 as in a video
it was done )
what device to select
2. when i filled the other fields , and clicked 'start' ,..... a message came .- reset isp mod
i pressed the reset button , but nothing happened .
tell me , it can be that usb to serial adapter cannot actually 'reset' after pressing reset button
and a serial cable can do , or something else possibilities

i am using 8051 development board from vegarobokit
and usb to serial adapter and flash magic as software .

89c51 does not support ISP. So you need a seperate programmer to program the IC, unlike P89v51 has the ISP capability... Moreover, as far as , dont use USB to serial while programing the controller... Use serial cable instead.. if it is laptop then use it,, but cant guarentee if it works properly.

See if you have 89c52 in the device list and try to use it.

AT89C51Rd2 also has ISP feature, along with reset pin u need to use PSEN pin also to enter in SIP mode
while reset PSEN pin should be low.
if u r using only TX & RX lines then serial to USB will work fine with ur laptop as well as desktop
if ur using DTR & RTS lines for directly entering ISP then u need to check, does ur USB converter supports these signals.
for vegarobokit, In their basic 8051 kit(single sided boars), TX & RX pins(P3.1 & P3.0) of microcontroller are not connected with MAX232
u check first if there is physical connection between MAX232 & 8051..??:cool:
If possible pls try to find out exact IC number den I can help u properly... :grin:

dont use sms or short hand typing skills in this forum... type the complete words by spending few more seconds. this is the last warning and further posts and thread of yours will be deleted without informing you if continued

---------- Post added at 07:20 ---------- Previous post was at 06:39 ----------

Dear Mr.CKShivram,

I'm surprised by your reply....
I think you are moderating the forum very well..
I'm not using any abusive language or not misusing the forum...
I'm also not cutting down any technical details...
wat ur pointing as a sms language is commonly known as internet language & commonly used over the web.
& this thing is completely readable & any computer literate person understand this language..
In my previous post i have used "u" instead of "YOU"
& "den" instead of "then',
& i dont think it is of much importance..
if you try to moderate grammatical mistake like this which doesn't change meaning of the post,
den in every post you have to raise the alarm...

I will be more happy if you raise alarm for me for my wrong posts or wrong guidance or
inappropriate data or abusive language or illegal material or irresponsible behavior...
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