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Mais ou menos.SammySam Escreveu:Azul liga na board.
Preto é no Master.
Cinza no Slave.
Atenção aos "jumpers" nos discos.
If two devices attach to a single cable, one is commonly referred to as a master and the other as a slave. The master drive generally appears first when the computer's BIOS and/or operating system enumerates available drives. On old BIOSes (486 era and older), the drives are often referred to by the BIOS as "C" for the master and "D" for the slave following the way DOS would refer to the active primary partitions on each.
If there is a single device on a cable, it should be configured as master. However, some hard drives have a special setting called single for this configuration (Western Digital, in particular). Also, depending on the hardware and software available, a single drive on a cable can work reliably even though configured as the slave drive (this configuration is most often seen when a CD ROM has a channel to itself).
A drive setting called cable select was described as optional in ATA-1 and has come into fairly widespread use with ATA-5 and later. A drive set to "cable select" automatically configures itself as master or slave, according to its position on the cable. Cable select is controlled by pin 28. The host adapter grounds this pin; if a device sees that the pin is grounded, it becomes the master device; if it sees that pin 28 is open, the device becomes the slave device.
This setting is usually chosen by placing a jumper on the "cable select" position, usually marked CS, rather than on the "master" or "slave" position. Note, pin 28 is only used by the drive to determine its position on the cable and thus whether it's the "master" or "slave"; it isn't in any way a "drive select" pin used when the host is issuing commands so if a drive is jumpered to "master" or "slave" its position on the cable doesn't have to match the pin 28 meaning of "master" and "slave".
With the 40-wire cable it was very common to implement cable select by simply cutting the pin 28 wire between the two device connectors; putting the slave device at the end of the cable, and the master on the "middle" connector. This arrangement eventually was standardized in later versions. If there is just one device on the cable, this results in an unused "stub" of cable, which is undesirable for physical convenience and electrical reasons. The stub causes signal reflections, particularly at higher transfer rates.
When the 80-wire cable was defined for use since ATAPI5/UDMA4, the master device goes at the end of the 18-inch (460 mm) cable (black connector), the middle-slave connector is grey, the blue connector goes onto the motherboard. So, if there is only one (master) device on the cable, there is no cable "stub" to cause reflections. Also, cable select is now implemented in the slave device connector, usually simply by omitting the contact from the connector body.
Both the 40-wire and 80-wire parallel-IDE cables share the same 40-socket connector configuration.


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