Maxq family user’s guide: maxq8913 supplement – Maxim Integrated MAXQ Family Users Guide: MAXQ8913 Supplement User Manual
Page 34
MAXQ Family User’s Guide:
MAXQ8913 Supplement
6-2
Table 6-1. Port Pin Special and Alternate Functions (continued)
The port pins on the MAXQ8913 operate the same as standard MAXQ port pins, with input/output states defined in
Table 6-2. Refer to the IC data sheet for specific voltage and current characteristics of port pins in input or output mode.
The port pins P0[7:0] on the MAXQ8913 have an additional operating mode available that allows the Schmitt input
triggers on individual pins to be enabled or disabled. When PID0.x is set to 1, the corresponding input bit PI0.x always
reads 0, regardless of the logic level that is currently present at the pin. When PID0.x is set to 0, the input bit PI0.x
operates normally.
Table 6-2. P1[3:0] Input/Output States (in Standard Mode)
Table 6-3. P0[7:0] Input/Output States (in Standard Mode)
PORT PIN
FUNCTION TYPE
FUNCTION
ENABLED WHEN
P1.1
Special
Serial Port 0 Transmit/Clock
Mode 0: REN set to 1 (until serial transmis-
sion completes)
Mode 1/2/3: SBUF is written (until serial
transmission completes)
P1.1
Special
SDA—I
2
C Data Line
I2CEN = 1 (overrides serial port Tx)
P1.2
Alternate
External Interrupt 10
(EIE1.2) EX10 = 1
P1.2
Alternate
Type B Timer 0 Input A (Counter Input)
C/TB = 1
P1.2
Special
Type B Timer 0 Output A (Clock Output)
C/TB = 0 and TB0E = 1
P1.3
Alternate
External Interrupt 11
(EIE1.3) EX11 = 1
P1.3
Alternate
Type B Timer 0 Input B
EXENB = 1
P1.3
Special
Type B Timer 0 Output B (Compare Output)
TBCR:TBCS<>00b
PD1.y
PO1.y
PORT PIN MODE
PORT PIN (Px.y) STATE
PI1.x READ VALUE
0
0
Input
Three-State
Depends on external sigal
0
1
Input
Weak pullup high
1 (unless overdriven externally)
1
0
Output
Strong drive low
0 (unless overdriven externally)
1
1
Output
Strong drive high
1 (unless overdriven externally)
PD0.x
PO0.x
PID0.x
PORT PIN MODE
PORT PIN (Px.y) STATE
PI0.x READ VALUE
0
0
0
Input
Three-State
Depends on external signal
0
0
1
No function
Three-State
0
0
1
0
Input
Weak pullup high
1 (unless overdriven externally)
0
1
1
Weak pullup
Weak pullup High
0
1
0
0
Output
Strong drive low
0 (unless overdriven externally)
1
0
1
Output
Strong drive low
0
1
1
0
Output
Strong drive high
1 (unless overdriven externally)
1
1
1
Output
Strong drive high
0
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