NXP Semiconductors PCA9955BTW-ARD, Руководство пользователя, Страница: 28 / 38

NXP Semiconductors
UM11761
PCA9955BTW-ARD evaluation board
7.4 Groups tab
Figure 20. Graphical interface – Groups / Brightness tab activated
The Groups contains nine secondary tabs. The default secondary tab from Channels
is Brightness (see the red left arrows in Figure 20 ). The secondary tabs set the internal
registers of PCA9955B device for four user defined groups of channels. Table 9 details
the names and address of the registers. See the PCA9955B datasheet for more details
about the internal registers which can be accessed from the Channels tab.
Secondary tab Picture in Register name Register HEX Remarks
Brightness Figure 20 GRPPWM #06h Read / Write
Blink Figure 21 GRPFREQ #07h Read / Write
Gain Figure 22 IREFGRP0 to IREFGR3 #2Bh, #2Fh, #33h, #37h Read / Write
Ramping Figure 23 RAMPRATE_GRPx #28h, #2Ch, #30h, #34h Read / Write
Step time Figure 24 STEPTIME_GRPx #29h, #2Dh, #31h, #35h Read / Write
Hold Figure 25 HOLDCNTL_GRPx #2Ah, #2Eh, #32h, #36h Read / Write
All Call I2C Figure 26 ALLCALLADR #43h Read / Write
Gradation Figure 27 GRADCNTL #3Eh Read / Write
Define Figure 28 GRADGRP_SELx #3Ah, #3Bh, #3Ch, #3Dh Read / Write / Write All
Table 9. Secondary tabs under Groups tab
The Write button sets individually the new values from the GUI to the internal registers of
the DUT. The WriteAll button sets globally the registers specified in Table 9 . The Read
button brings back to the GUI the values from the PCA9955B registers to the graphical
interface.
The GUI application is reflecting the PCA9955B internal registers, therefore the user
must fully understand the register map of the PCA9955B IC. In Section 8 a set of
instructions are provided, to help the user for quick check of the PCA9955BTW-ARD
board and understanding how to write the registers of the PCA9955B IC.
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
28 / 38