Introducing The Usb-1208Ls; Functional Block Diagram - Measurement Computing USB-1208LS User Manual

Introducing the USB-1208LS

The USB-1208LS features eight analog inputs, two 10-bit analog outputs, 16 digital I/O connections, and one
32-bit external event counter.
The analog inputs are software configurable for either eight 11-bit single-ended inputs, or four 12-bit
differential inputs. An on-board industry standard 82C55 programmable peripheral interface chip provides the
16 digital I/O lines in two 8-bit ports. You can configure each port independently for either input or output.
The USB-1208LS is powered by the +5 volt USB supply from your computer; no external power is required.
I/O connections are made to the device screw terminals.
The USB-1208LS device is compatible with both USB 1.1 and USB 2.0 ports. The speed of the device may be
limited when using a USB 1.1 port due to the difference in transfer rates on the USB 1.1 versions of the
protocol (low-speed and full-speed).

Functional block diagram

USB-1208LS functions are illustrated in the block diagram shown here.
Figure 1. Functional block diagram
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Chapter 1