| ??? 09/23/05 07:32 Read: times Msg Score: +1 +1 Good Answer/Helpful |
#101421 - USB is very different from RS232 Responding to: ???'s previous message |
The difference between USB and RS232 is like the difference between graphical programming and DOS programming. In the world of RS232, you control what goes down the wire directly. You can do anything you like, but you are responsible for handling everything. When you want to do USB, you have to do everything the host (PC) expects, and if you don't, the host will disconnect you.
A USB device must handle enumeration, handshaking and identification, and at the PC end you can't talk to your device directly, you need to go through a driver. I suggest that you buy 'USB Complete' and a development kit. I used the dev kit for the Atmel AT89C5131 successfully. This includes sample source code for a USB HID class device. As for speed, you would probably be looking at a full speed device, which runs at 12Mbps. The atmel devices include a PLL to generate the USB clock from a range of crystal frequencies. The only other two speeds supported by USB are low speed 1.5 Mbps and high speed 480 Mbps. |
| Topic | Author | Date |
| USB Interfacing With 8051 | 01/01/70 00:00 | |
| USB is very different from RS232 | 01/01/70 00:00 | |
| First Good Answer Is received! | 01/01/70 00:00 | |
| I have used from PDIUSBD12! | 01/01/70 00:00 | |
| USB - UART bridge | 01/01/70 00:00 | |
| Another Good Answer Is received! | 01/01/70 00:00 | |
| integrated or standalone | 01/01/70 00:00 | |
| Third Good Answer Is received! | 01/01/70 00:00 | |
| SiLabs F32x too | 01/01/70 00:00 | |
| the silabs f3xx chips are quite good but | 01/01/70 00:00 | |
| PDIUSB11 ! | 01/01/70 00:00 | |
| the hard way | 01/01/70 00:00 | |
| PDIUSB11 | 01/01/70 00:00 | |
| HR-USBUART | 01/01/70 00:00 | |
| SiLabs CP210x | 01/01/70 00:00 | |
Differences from RS232 | 01/01/70 00:00 |