Rainbow Electronics MAX1329 - Manual (Page 57)

MAX1329/MAX1330
12-/16-Bit DASs with ADC, DACs, DPIOs, APIOs,
Reference, Voltage Monitors, and Temp Sensor
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APIO Control Register
The Analog Programmable Input/Output (APIO) Control
register configures the modes of APIO1–APIO4.
APIO1–APIO4 I/O logic levels are referenced to AV
DD and
AGND (see Analog I/O in the Electrical Characteristics
table). APIO_ is configurable as a general-purpose input,
active-low wake-up input, general-purpose output, or seri-
al-interface, level-shifted buffered I/O.
AP_MD<1:0>: APIO_ Mode Configuration bits (default
= 00). AP_MD<1:0> configures the APIO_ mode
according to Table 30.
MSB LSB
NAME AP4MD1 AP4MD0 AP3MD1 AP3MD0 AP2MD1 AP2MD0 AP1MD1 AP1MD0
DEFAULT 0 0 0 0 0 0 0 0
Table 29. SPDT2 Switch Control Configuration
SPDT2 SWITCH STATE SPDT21
BIT
SPDT20
BIT
DPIO4 DPIO3 DPIO2 DPIO1
SNO2-TO-SCM2 STATE SNC2-TO-SCM2 STATE
0 0 0 0 0 0 Open Open
0 X X X X 1 Closed Closed
0 X X X 1 X Closed Closed
0 X X 1 X X Closed Closed
0 X 1 X X X Closed Closed
0 1 X X X X Closed Closed
1 0 0 0 0 0 Open Closed
1 X X X X 1 Closed Open
1 X X X 1 X Closed Open
1 X X 1 X X Closed Open
1 X 1 X X X Closed Open
1 1 X X X X Closed Open
Table 30. APIO_ Mode Bit Configuration
AP_MD1 AP_MD0 MODE DESCRIPTION
0 0 GPI Digital input. APIO_ logic level read from AP_LL register bit.
0 1 WUL Digital input. A falling edge on APIO_ sets the OSCE bit to 1 enabling the oscillator.
1 0 GPO Digital output. Set the APIO_ logic level by writing to the AP_LL register bit.
1 1 SPI
Digital input or output. The SPI mode functions differ for each APIO1–APIO4.
• APIO1 digital input. DOUT outputs the APIO1 logic level when CS is high, and
APIO1 is a GPI, when CS is low. Set the resistor pullup configuration with the
AP1PU bit.
• APIO2 digital output. APIO2 outputs the DIN logic level when CS is high and
becomes a GPO with the level set by AP2LL bit when CS is low.
• APIO3 digital output. APIO3 outputs the SCLK logic level when CS is high and
becomes a GPO with the level set by the AP3LL bit when CS is low.
• APIO4 digital output. APIO4 inverts and then outputs the CS logic level.