Zilog ZUSBOPTS - Manual (Page 19)

UM025603-0814 Individual GPIO Control
Zilog Educational Shields
User Manual
12
The following two examples demonstrate usage of this setpins command.
Example 1. The setpins PB FF ON command turns on all Port B bits
Example 2. The setpins PB FF OFF command turns these bits off
Individual GPIO Control
The setpins command that controls individual port bits is not available after the ZED
Test Shield has been initialized. Instead the ZED Test Shield, as controlled by the com-
mand shell, is primarily used to display text strings with the
LEDString command. Char-
acters will display on a 4x7 matrix instead of the more common 5x7 matrix because the
PA4 and PA5 bits are reserved for use by the UART. If the UART is not in use (i.e., the
USB console cable is not connected), the full 5x8 matrix will be available. Besides its
graphics capabilities, the shield can also be used to teach basic binary math.
Demonstrate the ZED Test Shield
Observe the following procedure to view a basic demonstration of the ZED Test Shield.
1. In Tera Term, enter the startshield leds command to initialize the ZED Test
Shield. An LEDS Shield started! message will appear, as shown in Figure 11.
Figure 11. ZED Test Shield initialization