Transfer types supported, Figure 3-1, Table 3-1 – Apple iMac User Manual
Page 29: Table 3-1 shows the pin assignments, Transfer types supported 3
C H A P T E R 3
Devices and Ports
USB Ports
29
Figure 3-1
USB Type A port and connector
The iMac computer provides 5-volt power at 500 mA for each of the two ports.
The USB ports support both low-speed and high-speed data transfers, at up to
1.5 Mbits per second and 12 Mbits per second, respectively. High-speed
operations requires the use of shielded cables.
Transfer Types Supported
3
The USB specification defines four data transfer types:
■
Control transfers, used for device configuration and initialization.
■
Bulk transfers, used for printers, scanners, modems, and other devices that
require accurate delivery of data with relaxed timing constraints.
Table 3-1
Pin assignments on the USB port
Pin
Signal name
Description
1
VCC
+5 VDC
2
D–
Data –
3
D+
Data +
4
GND
Ground