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I'm having some problem uploading my program into the microcontroller. I understand really good the bootstrap mode the how it work. But I thing my problem is that my microcontroller do not reset. My question is : What could I test to know if my 68hc11 is reset good and ready for receiving the programme? [Non-text portions of this message have been removed]

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Yes I build my own hardware on a testing board. My circuit work for a while but now I have a problem that I can't find. My reset circuit is done with a DS1233; 1 pin to ground, 1 pin to Vdd(+5v), 1 pin to the pin 17 on the MCU(68hc811e2) with a 1uf capacitor to the ground. Can you send me a schematic of your reset circuit? > The next, you can use LEDs to indicate RxD und TxD on your RS232 IC. => Can you send me a schematic or explaination? > After Reset there is a defined state. => What is this state and how I could test it? PD1 = 0101010101...???? Thank your for your reply!

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Hi Hugues, > Yes I build my own hardware on a testing board. My circuit work for a > while but now I have a problem that I can't find. Ah, that's strange. It worked for a while. Mmhh, are you sure, your Pins MODA und MODB are in right position? What was the last modification on the hardware? Or came the problem "over night" ? > My reset circuit is done with a DS1233; 1 pin to ground, 1 pin to > Vdd(+5v), 1 pin to the pin 17 on the MCU(68hc811e2) with a 1uf capacitor to > the ground. I picked up the datasheet and it's so simple. Pin 1 Ground Pin 2 Reset\ Pin 3 Vcc Pin 4 Ground But I think, that's not the problem. Just look with an oscilloscope on pin 17 on the MCU, then press reset. That's the best way to be sure if the hardware is ok. > Can you send me a schematic of your reset circuit? I just use a different IC and it doesn't really matter what kind of reset IC you are using. They all work fine and million times. > > The next, you can use LEDs to indicate RxD und TxD on your RS232 IC. => > Can you send me a schematic or explaination? Take two LEDs, from Pin 20 and 21 (Kathode) over resister 220R to Vdd(+5V). If you press the reset button and hold it down, both LEDs are off. Release the reset button, RxD is still off and TxD in on. Voila, if so, the MCU is ready to connect via RS232. > could test it? PD1 = 0101010101...???? You can look with the oscilloscope on pin 20, 21 for aktivities after reset. James

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