When configuring the MAX6954 Drivers for different combinations of monocolor or bicolor, 7-segment/14-segment/16-segment digits, Tables 37-40 from the MAX6954 datasheet are the best places to start.
Pay attention to the following points:
- The IC has 4 output Slots, and each contains two cathode drivers CC_ and CC_+1. These are from output pins O0-O8.
- Every driver (CC_ or CC_+1) in a Slot is capable of driving up to two 7-segment monocolor digits, or one 14-segment monocolor digit. If a digit is bi-color, one can expect half the driver capability.
- Tables 37-40 indicate the different combinations each Slot may drive.
- In these tables, rows indicate the output pin O_ connection in each configuration.
- Columns indicate a full configuration to drive the types of digits named in the column's type cell.
- Some Slots in these Tables indicate only one driver being used, while some slots indicate both.
- If a column indicates one driver (e.g. CC_) being used, a different column may be simultaneously used for the other driver (e.g. CC_ ± 1).
- Only one column indicating both drivers (CC_ and CC_+1) may be selected and used.
Examples of valid configurations can be found in Figures 1a and 1b below:
Figure 1a (left) and 1b (right): Two valid, mutually exclusive configurations for Slot 2 of MAX6954. Both taken from Table 38 of the MAX6954 datasheet.
O0-O18 are each of the IC's output pins, and each cell represents the pin of the digit being driven that O0-O18 from the MAX6954 connects to. O0-O8 are capable of driving a digit's common cathode, and thus are named CC0-CC8 when being used for this purpose. The same pin can be used as a cathode driver (e.g. CC0 in Table 37) for one digit and as a segment anode driver (e.g. 1a in Table 38) for another.
In addition, when selecting the driver, pay attention to the associated bits in the Digit Type register (0x0C) given at the bottom of Tables 37-40. These bits must be set according to the columns chosen in the table. For example, in the diagrams above, the configuration on the left will use D2 = 0, D3 = 1. The configuration on the right will use D2 = D3 = 0. This register must be set according to the chosen configuration of digits.