| ??? 11/25/04 10:38 Read: times |
#81901 - Google not so helpful Responding to: ???'s previous message |
Muhammad Munib said:
Sir i have studied about this but problem is i m confused about the terms. At some places i got the impression that they are same and at other places i felt that no they are different I think you're probably right - with terms as common as these, Internet search engines are not very helpful in finding sites that define these terms rather than just mention them! What you really want is an electronics dictionary site - you should have come across a few in your googling? You are also right that many internet sites are very sloppy in their use of terminology - and use terms like this in inapproproate or even downright incorrect ways! eg, http://www.8052.com/forum/read.phtml?id=46426 So it is good that you're asking! UART = Universal Asynchronous Receiver/Transmitter That is correct. A UART is, essentially, a physical component[1]. It interfaces parallel data (eg, a microcontroller bus) to an Asynchronous serial format - therefore, it must handle start bit generation & detection, etc. It may also automatically do things like parity generation & checking, and flow control. Although a UART is required for RS232, a UART alone is not sufficient for RS232: the RS232 specification includes other requirements such as bipolar signal voltages, etc. A UART needs to be used in conjunction with a Transceiver to achieve a full RS232 interface (the MAX232 is the classic - the are plenty of equivalents & substitutes). http://www.8052.com/forum/read.phtml?id=81019 Then there's the USART = Universal Synchronous/Asynchronous Receiver/Transmitter. As the name implies, it's like a UART, but with added support for Synchronous serial data. (Note that the RS232 spec specifies both Synchronous and Asynchronous formats). SPI=serial port interface No. SPI = Serial Peripheral Interface. SPI is a Protocol - not a component (unlike the UART). SPI defines a 3-wire synchronous serial bus interface. It is a Motorola trademark. Jan Axelson has an article comparing & contrasting different serial interfaces: http://www.8052.com/forum/read.phtml?id=25430 See also: http://www.8052.com/forum/read.phtml?id=74858 [1] Of course, these days, a UART is not necessarily a separate component; eg, the 8051 has a UART built-in. You can also implement a UART in software - search here for "soft UART" for further details. |
| Topic | Author | Date |
| serial port/UART/SPI? | 01/01/70 00:00 | |
| Google first | 01/01/70 00:00 | |
| RE:Google first | 01/01/70 00:00 | |
| UART/SPI | 01/01/70 00:00 | |
| correction | 01/01/70 00:00 | |
| More on SPI | 01/01/70 00:00 | |
| SPI vs UART | 01/01/70 00:00 | |
| That would be I2C? | 01/01/70 00:00 | |
| UART and SPI, the main difference | 01/01/70 00:00 | |
| The real difference... | 01/01/70 00:00 | |
| rs232c | 01/01/70 00:00 | |
| Component vs Protocol | 01/01/70 00:00 | |
| Not all UARTs are RS-232! | 01/01/70 00:00 | |
| 232 is more than just a UART | 01/01/70 00:00 | |
| Nice discussion going | 01/01/70 00:00 | |
| Google not so helpful | 01/01/70 00:00 | |
| SPI - Correction | 01/01/70 00:00 | |
| SPI | 01/01/70 00:00 | |
| SPI or SPI?! | 01/01/70 00:00 | |
| Atmel | 01/01/70 00:00 | |
| OT: ISO and interfaces | 01/01/70 00:00 | |
| SPI | 01/01/70 00:00 | |
| Serial Port - ambiguous! | 01/01/70 00:00 | |
| SPI STANDARD | 01/01/70 00:00 | |
| try | 01/01/70 00:00 | |
| Getting back to the original subject | 01/01/70 00:00 | |
| Not quite.... | 01/01/70 00:00 | |
| Picky, picky,... | 01/01/70 00:00 | |
| Chapter & Verse | 01/01/70 00:00 | |
| Hayes Commands | 01/01/70 00:00 | |
| nice discussion | 01/01/70 00:00 | |
| Where is Mohammad | 01/01/70 00:00 | |
| Summary of Buses etc | 01/01/70 00:00 | |
RS232 is NOT a bus! | 01/01/70 00:00 |