Cirrus Logic EP93xx - Manual (Page 799)

DS785UM1 28-9
Copyright 2007 Cirrus Logic
GPIO Interface
EP93xx User’s Guide
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28
10. COL[7:0] are the Key Matrix column pins.
Note: The various functional modes described in Table 28-4 are selected via bits set in the
DeviceCfg register in Syscon. See Chapter 5 , “DeviceCfg” on page 5-25 for additional
register information.
When the GPIO port signals are not explicitly mapped to a device pin, the inputs will continue
to monitor the pin while outputs are disconnected. For example, when the Key Matrix block
has control of the ROW pins, GPIO port C inputs still monitor the state of the ROW pins.
Another level of functional muxing is applied to several EGPIO pins. The Syscon DeviceCfg
register bits RonG, MonG, TonG, HC3EN, HC1EN, and map different functionality to the
EGPIO pins:
• MonG maps RI (modem Ring Indicator) onto EGPIO[0].
• RonG maps CLK32K, the 32 KHz clock monitor output for RTC calibration, onto
EGPIO[1].
• TonG maps TENn, the RS485 transmit enable output, onto EGPIO[3].
• Both HC3EN and HC1EN map the synchronous HDLC clock onto EGPIO[3].
Some GPIO signals are used as inputs by other functional blocks. EGPIO[2:1] are routed to
the DMA controller to allow for external DMA requests. IDE interface input signals DMARQ
and DASPn are EGPIO[2] and EGPIO[15], respectively.
28.2 Registers
Table 28-5. GPIO Register Address Map
Address Read Location Type Write Location Reset Value
0x8084_0000 PADR R/W PADR Note 1
0x8084_0004 PBDR R/W PBDR Note 1
0x8084_0008 PCDR R/W PCDR Note 1
0x8084_000C PDDR R/W PDDR Note 1
0x8084_0010 PADDR R/W PADDR 0x00
0x8084_0014 PBDDR R/W PBDDR 0x00
0x8084_0018 PCDDR R/W PCDDR 0x00
0x8084_001C PDDDR R/W PDDDR 0x00
0x8084_0020 PEDR R/W PEDR Note 2
0x8084_0024 PEDDR R/W PEDDR 0x03
0x8084_0028 RSVD - RSVD -
0x8084_002C RSVD - RSVD -
0x8084_0030 PFDR R/W PFDR Note 1
0x8084_0034 PFDDR R/W PFDDR 0x00
0x8084_0038 PGDR R/W PGDR Note 1
0x8084_003C PGDDR R/W PGDDR 0x0C
0x8084_0040 PHDR R/W PHDR Note 1
0x8084_0044 PHDDR R/W PHDDR 0x00
0x8084_0048 RSVD - RSVD -
0x8084_004C GPIOFIntType1 R/W GPIOFIntType1 0x00