NXP Semiconductors PCA9955BTW-ARD, Руководство пользователя, Страница: 23 / 38

NXP Semiconductors
UM11761
PCA9955BTW-ARD evaluation board
7.2 Global
Figure 12. Graphical interface – Global / Brightness tab activated
The Global contains two secondary tabs. The default secondary tab is Brightness (see
the red left arrows in Figure 12 ). The two secondary tabs sets the “PWMAL” (44h) and
“IREFALL” (45h) internal registers of PCA9955B IC. The registers assure the overall
control of the LEDs driven by the PCA9955B driver. The registers are 7-bit wide and can
be set from the interface in four ways:
• Typing the hexadecimal value in the corresponding “Hex” box;
• Typing the decimal value in the corresponding “Dec” box;
• Setting each bit of the register with values of 0 and 1;
• Using the slider;
Table 7 details the names and address of the registers:
Secondary tab Picture in Register name Register address Remarks
Brightness Figure 12 PWMALL #44h Write only
Gain Figure 13 IREFALL #45h Write only
Table 7. Secondary tabs under Global
The
Write
button send the value from the GUI to the internal registers of the DUT.
UM11761 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2022. All rights reserved.
User manual Rev. 1.0 — 18 March 2022
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