Specifications

Élan™SC310 Microcontroller Data Sheet 61
PRELIMINARY
ALTERNATE PIN FUNCTIONS SELECTED VIA FIRMWARE
The following tables contain brief descriptions of the alternate pin functions/names and the pin names of the default
function that the alternate function replaces. These alternate functions are selected via system firmware only.
SRAM Interface
This alternate function is configured by setting bit 0 of the Miscellaneous 6 Register, Index 70h.
Unidirectional/Bidirectional Parallel Port
This alternate function is configured via selecting either the Normal Bidirectional mode configuration or the EPP
mode configuration for the parallel port in the Function Enable 1 Register, Index B0h.
X1OUT [BAUD_OUT] Clock Source
The internal clock source driving out on this pin is configured via register bits of the Function Enable Registers,
Indexes B0h and B1h.
Notes:
The default function of this pin is that no clock is driven out and the pin is tri-stated.
Table 28. SRAM Interface
SRAM Pin Name Pin Type
SRAM Interface Pin
Description/Notes
Default Pin
Name/Function
Pin No.
[SRCS0]
O
SRAM Bank 0 Chip Select. Low Byte CAS0L
6
[SRCS1]
O
SRAM Bank 0 Chip Select. High Byte CAS0H
7
[SRCS2]
O
SRAM Bank 1 Chip Select. Low Byte CAS1L
4
[SRCS3]
O
SRAM Bank 1 Chip Select. High Byte CAS1H
5
Table 29. Bidirectional Parallel Port Pin Description
Bidirectional Pin
Name
Pin Type Bidirectional Parallel Port Pin
Description/Notes
Default Pin
Name/Function
Pin No.
[PPDCS
]
O
Parallel Port data register address decode PPDWE
90
Table 30. X1OUT Clock Source Pin Description
BAUD_OUT Pin Name Pin Type
X1OUT [BAUD_OUT] Pin
Description/Notes
Default Pin
Name/Function
Pin No.
[BAUD_OUT]
O
Serial baud rate clock X1OUT
200