Intel 386 - Manual (Page 265)

Intel386™ EX EMBEDDED PROCESSOR USER’S MANUAL
10-22
The peripheral pin selection registers (P3CFG and PINCFG) determine whether each counter’s
OUTn signal is connected to its TMROUTn pin. See Figure 10-1 for the TCU signal connections.
For details on the P3CFG and PINCFG registers see Figure 10-23 and Figure 10-24. The counter
output signals are automatically connected to the interrupt control unit. Counter 1’s output signal
(OUT1) is automatically connected to DMA channel 0, and counter 2’s output signal (OUT2) is
automatically connected to DMA channel 1.
Use P3CFG bits 0 and 1 to connect TMROUT0 and TMROUT1 to package pins.
Figure 10-23. Port 3 Configuration Register (P3CFG)
Port 3 Configuration
P3CFG
(read/write) Expanded Addr:
ISA Addr:
Reset State: F824H
—
00H
7 0
PM7 PM6 PM5 PM4 PM3 PM2 PM1 PM0
Bit
Number
Bit
Mnemonic
Function
7 PM7 Pin Mode:
0 = Selects P3.7 at the package pin.
1 = Selects COMCLK at the package pin.
6 PM6 Pin Mode:
0 = Selects P3.6 at the package pin.
1 = Selects PWRDOWN at the package pin.
5 PM5 Pin Mode:
0 = Selects P3.5 at the package pin.
1 = Connects master IR7 to the package pin (INT3).
4 PM4 Pin Mode:
0 = Selects P3.4 at the package pin.
1 = Connects master IR6 to the package pin (INT2).
3 PM3 Pin Mode:
0 = Selects P3.3 at the package pin.
1 = Connects master IR5 to the package pin (INT1).
2 PM2 Pin Mode:
0 = Selects P3.2 at the package pin.
1 = Connects master IR1 to the package pin (INT0).
1 PM1 Pin Mode:
See Table 5-1 on page 5-8 for all the PM1 configuration options.
0 PM0 Pin Mode:
See Table 5-1 on page 5-8 for all the PM0 configuration options.