Author Topic: ISP Entry using DTR and RTS  (Read 3801 times)

Nor_Ain

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ISP Entry using DTR and RTS
« on: June 07, 2013, 04:02:53 pm »
Hello all,

I'm try to implement the DTR and RTS signal to enter the ISP mode and RESET.
However, I'm facing a problem with the DTR and RTS signal. Do i need to connect the DTR and RTS from RS232 directly into 74LS125 chip? Or I need a
RS232 tranceiver chip to connect these  DTR and RTS?

Any help highly appreciated.

Thanks.

Andy Ayre

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Re: ISP Entry using DTR and RTS
« Reply #1 on: June 10, 2013, 09:32:39 am »
RS232 does not use TTL logic levels. You can either use an RS232 transceiver or you can use transistors. Please see the schematics of the Keil evaluation boards on keil.com for ideas.

Andy
Embedded Systems Academy, Inc.
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govind

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Re: ISP Entry using DTR and RTS
« Reply #2 on: January 02, 2014, 09:54:30 am »
please send me ciruit diagram of flash magic programmer.

Andy Ayre

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Re: ISP Entry using DTR and RTS
« Reply #3 on: January 02, 2014, 10:05:42 am »
We recommend you start off with an evaluation board from a well known manufacturer. They always include circuit diagrams.

Andy
Embedded Systems Academy, Inc.
support at esacademy dot com