Maxim Integrated MAXQ Family Users Guide: MAXQ2010 Supplement - Manual (Page 39)

MAXQ Family User’s Guide:
MAXQ2010 Supplement
6-1
ADDENDUM TO SECTION 6: GENERAL-PURPOSE I/O MODULE
The MAXQ2010 provides up to 55 port pins for general-purpose I/O that are grouped into logical ports P0 to P6. Each
of these port pins has the following features:
• CMOS output drivers
• Schmitt trigger inputs
• Optional weak pullup to DVDD when operating in input mode
Many of the port pins on the MAXQ2010 are also multiplexed with special and alternate functions as listed below.
All these functions are disabled by default with the exception of the debug port interface pins, which are enabled by
default following any reset. The behavior of these functions breaks down into two overall categories.
• Special functions override the PD and PO settings for the port pin when they are enabled. Once the special func-
tion takes control, normal control of the port pin is lost until the special function completes its task or is disabled.
Examples of special functions include serial port 0 transmit and LCD segment drive.
• Alternate functions operate in parallel with the PD and PO settings for the port pin, and generally consist of input-
only functions such as external interrupts. When an alternate function is enabled for a port pin, the port pin’s output
state is still controlled in the usual manner.
Table 6-1. Port Pin Special and Alternate Functions
PORT PIN FUNCTION TYPE FUNCTION ENABLED WHEN
P0.0 Special Analog LCD Segment SEG0 DPE = 1, PCF0 = 1, and EX0 = 0
P0.0 Alternate External Interrupt 0 (EIE0.0) EX0 = 1
P0.1 Special Analog LCD Segment SEG1 DPE = 1, PCF0 = 1, and EX1 = 0
P0.1 Alternate External Interrupt 1 (EIE0.1) EX1 = 1
P0.2 Special Analog LCD Segment SEG2 DPE = 1, PCF0 = 1, and EX2 = 0
P0.2 Alternate External Interrupt 2 (EIE0.2) EX2 = 1
P0.3 Special Analog LCD Segment SEG3 DPE = 1, PCF0 = 1, and EX3 = 0
P0.3 Alternate External Interrupt 3 (EIE0.3) EX3 = 1
P0.4 Special Analog LCD Segment SEG4 DPE = 1, PCF0 = 1, and EX4 = 0
P0.4 Alternate External Interrupt 4 (EIE0.4) EX4 = 1
P0.5 Special Analog LCD Segment SEG5 DPE = 1, PCF0 = 1, and EX5 = 0
P0.5 Alternate External Interrupt 5 (EIE0.5) EX5 = 1
P0.6 Special Analog LCD Segment SEG6 DPE = 1, PCF0 = 1, and EX6 = 0
P0.6 Alternate External Interrupt 6 (EIE0.6) EX6 = 1
P0.7 Special Analog LCD Segment SEG7 DPE = 1, PCF0 = 1, and EX7 = 0
P0.7 Alternate External Interrupt 7 (EIE0.7) EX7 = 1
P1.0 Special Analog LCD Segment SEG8 DPE = 1 and PCF1 = 1
P1.1 Special Analog LCD Segment SEG9 DPE = 1 and PCF1 = 1
P1.2 Special Analog LCD Segment SEG10 DPE = 1 and PCF1 = 1
P1.3 Special Analog LCD Segment SEG11 DPE = 1 and PCF1 = 1
P1.4 Special Analog LCD Segment SEG12 DPE = 1 and PCF1 = 1
P1.5 Special Analog LCD Segment SEG13 DPE = 1 and PCF1 = 1
P1.6 Special Analog LCD Segment SEG14 DPE = 1 and PCF1 = 1
P1.7 Special Analog LCD Segment SEG15 DPE = 1 and PCF1 = 1
P2.0 Special Analog LCD Segment SEG16 DPE = 1 and PCF2 = 1
P2.1 Special Analog LCD Segment SEG17 DPE = 1 and PCF2 = 1
P2.2 Special Analog LCD Segment SEG18 DPE = 1 and PCF2 = 1