Maxim MAX3421E, Руководство по программированию, Страница: 2 / 63

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About This Programming Guide
The MAX3421E is a dual-role USB controller, which can be programmed either as a USB
peripheral or host. As a peripheral, the MAX3421E’s operation is identical to the MAX3420E
peripheral-only part. If you plan to use the MAX3421E only as a USB peripheral that runs
existing MAX3420E code, keep the HOST bit set to 0 (the default), and consult the
MAX3420E
Programming Guide
for programming details.
If you plan to use the MAX3421E only as a USB peripheral but want to take advantage of the
new peripheral features, read about the added registers R21 to R24 and the added bits
PULSEWID1/0, SEPIRQ, and HOST in this
Programming Guide
. Then consult the
MAX3420E
Programming Guide
.
Most MAX3421E users will want programming details for host operation, which is the purpose
of this guide. It is, therefore, quite logical to present only the bits and registers that apply to host
operation (
Table 1 ). For convenient reference, however, Table 2 shows all the register bits for
both host and peripheral operation.
Table 1 serves as a navigation tool if you are viewing this document in electronic form. This
table contains links to document pages that describe the linked registers and bits.