Debugging via USB

The SILabs derivatives (f0x-f2x) are wondeful chips that be debugged via the USB interface to a JTAG interface that is supported by Keil and as opposed to the deviates, (most) everything is as we know and love it.

Watch out for the SILabs deviates (f3x - up) they do, indeed, have a "JTAG inteface" and can be debugged via the USB interface to a JTAG interface that is supported by Keil. They do have a '51 core, but the peripherals will drive you crazy, all peripherals are different from everything you know.
when working with SILabs deviates, experience is not an advantage, it is a hindrance

Both derivatives and deviates program and debug via JTAG which is generated by a dongle ($69 if I recall) you drive via USB. The great thing about the SILabs JTAG is that it gives you ICE functionality.

Erik

PS do not buy the dongle, pick a devboard, it comes with the dongle and is just a few dollars more.

The SILabs derivatives (f0x-f2x) are wondeful chips that be debugged via the USB interface to a JTAG interface that is supported by Keil and as opposed to the deviates, (most) everything is as we know and love it.

Watch out for the SILabs deviates (f3x - up) they do, indeed, have a "JTAG inteface" and can be debugged via the USB interface to a JTAG interface that is supported by Keil. They do have a '51 core, but the peripherals will drive you crazy, all peripherals are different from everything you know.
when working with SILabs deviates, experience is not an advantage, it is a hindrance

Both derivatives and deviates program and debug via JTAG which is generated by a dongle ($69 if I recall) you drive via USB. The great thing about the SILabs JTAG is that it gives you ICE functionality.

Erik

PS do not buy the dongle, pick a devboard, it comes with the dongle and is just a few dollars more.

Thanks for the info re. JTAG. More specifically, with regards to USB I was hoping that I could use a device with an on-chip USB (there are plenty of them, Atmel & Philips for example) and use a direct USB connection to the PC for debugging (no dongle). After all, the Atmel devices can be flash programmed directly via USB using FLIP. OK, so why would I use a device with USB if I did'n want to use the USB in the application, but can't because I'm "wasting it on debugging"? I'm just weighing up my options.

is that, if a device were to have "'direct USB debugging", the USB would have to be "hard coded" in the chip. I doubt such a chip would sell very well.

Erik

....unless it had a variant of Flashmon (or something similar) installed using FLIP that would configure the USB appropriately. Maybe this is a project for one of my students.....

how would you load it?
if you have to find a means of loading it (in ISP mode) why not use the same means to debug?

Erik