Messages

I am not sure I understand the waveforms I need to use for P89LPC930
The LPC930 does not have a PSEN pin and the waveforms show a PSEN pin.
The circuit I have is very similar to the circuit shown for P89LPC930, however it is using a CP2102 USB to serial converter for connecting to the PC.
The USB to serial outputs the Tx (connected to CPU Rx pin), the Rx (connected to CPU Tx pin) and DTR and RTS signals connected directly to the gates of the 74HC02. they are connected without any clamping resistors since the CP2102 outputs them in TTL levels.

Is there any special setup I need to do in the Flashmagic so it will control the Reset and Vdd lines using RTS and DTR?

I am sorry but the application note is not clear enough what to do (It does not even mention my device, I just assumed it works like P89LPC932), I hope this circuit is right for my device.

Can you tell me what waveforms should I expect on DTR, RTS and Tx (of the PC) when trying to read device signature?
It is hard to debug a circuit when I have no idea what waveforms should I expect.
I will use a two probe scope next time, but I need to know the waverforms I should expect.

It does not seem to work.

I have followd the application note for FlashMagic programming.
When trying to read device signature:
DTR Starts high and going low for several times
RTS Starts high and going low for several times

I have a scope with only one probe so I can not tell the relationship between these signals.

ן have looked at the user manual.
I understand that I have to control the Vdd and Reset signal.
My question is regarding the flash magic software, what lines does it control.

I am designing a circuit that will contain P89LPC930 and a Silicon Labs CP2102 USB to Serial converter.
How should I connect the output of the CP2102 (It has Tx, Rx, RTS, CTS and other handshake lines).