SP37E760 Datasheet, PDF (44/78 Pages) SMSC Corporation – 3.3 V I/O CONTROLLER FOR EMBEDDED APPLICATIONS

6.3 Parallel Port
Direct parallel port power management is controlled by the Parallel Port Power bit in Configuration Register 1. Refer
to section CR01 on page 48 for more information.
Parallel port Auto Power Management is enabled by the Parallel Port Enable bit in Configuration Register 7 (see
section CR07 on page 51). When set, this bit allows the ECP or EPP logical parallel port blocks to be placed into the
powerdown state as follows:
The EPP logic is in powerdown under any of the following conditions:
1. EPP is not enabled in the configuration registers.
2. EPP is not selected through ecr while in ECP mode.
The ECP logic is in powerdown under any of the following conditions:
1. ECP is not enabled in the configuration registers.
2. SPP, PS/2 Parallel port or EPP mode is selected through ecr while in ECP mode.
The parallel port logic can change powerdown modes when the ECP mode is changed through the ecr register or
when the parallel port mode is changed through the configuration registers.
SMSC DS – SP37E760
Page 44
Rev. 04/13/2001