Specifications

62 Élan™SC310 Microcontroller Data Sheet
PRELIMINARY
PC/XT Keyboard
The PC/XT keyboard functionality is enabled via bit 3 of PMU Control 3 Register, Index ADh.
14-MHz Clock Source
Setting bit 3 of Miscellaneous 3 Register, Index BAh, enables the 14.336 MHz clock signal on the parallel port pin
AFDT.
Table 32. 14-MHz Clock Source
Table 31. XT Keyboard Pin Description
PC/XT Keyboard Pin
Name
Pin Type
PC/XT Keyboard Pin
Description/Notes
Default Pin
Name/Function
Pin No.
[XTDAT]
I/O
Keyboard data 8042CS
75
[XTCLK]
I/O
Keyboard clock SYSCLK
45
14-MHz
Pin Name
Pin Type
14-MHz Clock Pin
Description/Notes
Default Pin
Name/Function
Pin No.
[X14OUT]
O
14.336-MHz Clock AFDT
80