So why do you think MAX7219 is not covered by that app note?
Maxim uses one datasheet for both MAX7221 and MAX7219. In that datasheet, they also specify (page 6):
MAX7219/MAX7221 Differences
The MAX7219 and MAX7221 are identical except for two parameters: the MAX7221 segment drivers are
slew-rate limited to reduce electromagnetic interference (EMI), and its serial interface is fully SPI compatible