Rs232

[dapack69]

Could someone please tell me what this is used for?

 

[highfigh]

It's used for controlling Audio/Video equipment, among other things. Serial ports are basically a dead issue on laptop computers but it was used for years.

http://en.wikipedia.org/wiki/RS-232

 

[lsiberian]

Could someone please tell me what this is used for?

Rs232 is a standard widely used for controlling devices. These days you need a USB to RS232 converter to use it, but it's still widely used and pretty simple. We used it in many of our engineering projects to communicate with our automated machines.

In audio it's used to upload firmware or interfacing eqing.

 

[njedpx3]

It was an early-on communications standard in the 70s

Could someone please tell me what this is used for?

It was an early-on communications standard when mainframes began supporting telecommunications in the early 70's

It was a 25 wire standard that supported half-duplex, full duplex communications up to 19.2 K bps. The wires and defined protocol defined the interface between DTE ( data terminal equipment) and DCE (data communications equipment). Most data communications at that time had one start bit, eight data bits and one stop bit so 19.2 K bps ( bit per second)translated to 1,920 characters per second, very very slow by todays standards. The exception which was actually the first widely used communications was 110 baud which had two stop bits for a blazing speed of 10 characters per second. Normal phone lines were used either with a modem or acoustic coupler. Everything was text only and email or the Internet hadn't been invented ( even ARPA net was in its infancy). RS232 continued on in some instances through the early 90s as a terminal emulation interface into equipment to provide update support. However, even that support has gone to Internet based. RS232 was later replaced by V.35 which provided support for up to 56 kpbs. Then came 4 meg bits per second Token Ring LAN (Local Area Networks) and 10 meg Ethernet with CSMA/CD carrier sense multiple access with collision detection.

 

[dapack69]

Thank you for the responses. The main reason I ask is I see some A/V's have it and others do not. I guess its something I will never use.

 

[lsiberian]

It was an early-on communications standard when mainframes began supporting telecommunications in the early 70's

It was a 25 wire standard that supported half-duplex, full duplex communications up to 19.2 K bps. The wires and defined protocol defined the interface between DTE ( data terminal equipment) and DCE (data communications equipment). Most data communications at that time had one start bit, eight data bits and one stop bit so 19.2 K bps ( bit per second)translated to 1,920 characters per second, very very slow by todays standards. The exception which was actually the first widely used communications was 110 baud which had two stop bits for a blazing speed of 10 characters per second. Normal phone lines were used either with a modem or acoustic coupler. Everything was text only and email or the Internet hadn't been invented ( even ARPA net was in its infancy). RS232 continued on in some instances through the early 90s as a terminal emulation interface into equipment to provide update support. However, even that support has gone to Internet based. RS232 was later replaced by V.35 which provided support for up to 56 kpbs. Then came 4 meg bits per second Token Ring LAN (Local Area Networks) and 10 meg Ethernet with CSMA/CD carrier sense multiple access with collision detection.

I thought internet was invented in 1969 along with sex, government moon landing conspiracies, rock&roll and drugs.

But I'm a wee lad compared to you. I'm just barely married. Though I do remember LAN lines.

 

[highfigh]

I thought internet was invented in 1969 along with sex, government moon landing conspiracies, rock&roll and drugs.

But I'm a wee lad compared to you. I'm just barely married. Though I do remember LAN lines.

ARPA net came along in 1959, not '69. My high school was already renting time on a Sperry Univac before I got there in '71.

 

[lsiberian]

ARPA net came along in 1959, not '69. My high school was already renting time on a Sperry Univac before I got there in '71.

There seems to be some confusion so i'll clarify the statement.

the first documented message on ARPAnet was October 29,1969. I had to take a test on the Internet history in college.

In 71 email was invented. I bet in 69 everyone thought the moon landing was the pivotal event. The Internet is nearly 40 years old!

 

[highfigh]

There seems to be some confusion so i'll clarify the statement.

the first documented message on ARPAnet was October 29,1969. I had to take a test on the Internet history in college.

In 71 email was invented. I bet in 69 everyone thought the moon landing was the pivotal event. The Internet is nearly 40 years old!

I guess I assumed that since the concepts and "beginning" of their network was in '59, it would have been up and running sooner. For some reason, when I took my networking class, the book made it seem that it was operational much before '69.

When I was originally in school, and keep in mind that this was an engineering school, the computer department rented time from the same computer as my high school and we worked with interactive Fortran. PCs were in the somewhat near future and we used punch cards and tape strips for our programs. The modem used a dial phone, with a cradle for the handset. After I was out, all heck broke loose in technology and after the new library was built, one donor fired up for 300 IBM PCs.