(NMIs), wake-ups, or activities for the power manage-
ment unit. They can also be used as I/O or memory
chip selects.
Serial Port
The ÉlanSC400 and ÉlanSC410 microcontrollers in-
clude an industry-standard 16550A UART. The UART
can be used to drive a standard 8-pin serial interface or
a 2-pin infrared interface. The serial interface and infra-
red interface signals are available on the ÉlanSC400
and ÉlanSC410 microcontrollers at all times, though
only one is available at any given time.
Infrared Port for Wireless Communication
The ÉlanSC400 and ÉlanSC410 microcontrollers sup-
port infrared data transfer. This support consists of
adding additional transmit and receive serializers as
well as a controlling state machine and DMA interface
to the internal UART.
The UART powers up as a 16450-compatible device. It
can be switched to and from the FIFO (16550) mode
under software control. In the FIFO mode, the receive
and the transmit circuitry are each enhanced by sepa-
rate 16-byte FIFOs to off-load the CPU from repetitive
service routines.
The integrated infrared port includes these features:
■ Low-speed mode supports all bit rates from UART,
up to 115 Kbit/s
■ High-speed mode transfers 1.152 Mbit/s using DMA
The serial port includes the following features:
Dual PC Card Controller
(ÉlanSC400 Microcontroller Only)
■ Eight-pin interface: serial in, serial out, two modem
control lines, and four modem status lines
The PC Card host bus adapter included on the
ÉlanSC400 microcontroller conforms to PCMCIA Stan-
dard Release 2.1. It provides support for two sockets,
each implementing the PC Card memory and I/O inter-
faces. The PC Card controller is not supported on the
ÉlanSC410 microcontroller.
■ Separately enabled receiver line status, receiver
data, character timeout, transmitter holding register,
and modem status interrupts
■ Baud-rate generator provides input clock divisor
from 1 to 65535 to create 16x clock
■ 5-, 6-, 7-, or 8-bit data
The PC Card controller includes the following features:
■ Even, odd, stick, or no parity generation and
■ ExCA-compliant, 82365-register-set compatible
■ 8-bit and 16-bit data bus
checking
■ 1, 1-1/2 or 2 stop-bit generation
■ Break generation/detection
■ DMA transfers between I/O PC cards and system
DRAM
■ Ten available memory windows, five per socket
Keyboard Interfaces
The integrated keyboard controller has the following
features:
Of the two PC Card sockets supported, only one is
available in all modes of operation. The second socket
is multiplexed with the parallel port and GPIO features.
■ Matrix keyboard support with up to 15 rows and 8
columns
Register set compatibility with the 82365SL PC Card
Interface Controller is maintained where features are
common to both controllers.
■ Hardware support for software emulation of the
System Control Processor (SCP) emulation logic
Of the ten memory windows available, six are dedi-
cated to the PC Card controller and four are shared
with memory mapping system (MMS) Windows C–F.
■ XT keyboard interface
Programmable General-Purpose
Inputs and Outputs
Two of the three ROM/Flash memory chip selects can
be remapped to a PC Card socket via pinstrap or soft-
ware control. This feature supports reprogramming of
soldered down Flash memory boot devices and also
simplifies testing of BIOS/XIP OS code.
The chip supports several general-purpose I/O signals
(GPIOs) that can be used on the system board. There
are two classifications of GPIO available: the GPIOx
signals, which are programmable as inputs or outputs
only, and the GPIO_CSx signals.
Graphics Controller for CGA-Compatible
Text and Graphics
(ÉlanSC400 Microcontroller Only)
The GPIO_CSx signals have many programmable op-
tions. They can be configured as chip selects. As out-
puts, these signals are individually programmable to be
High or Low for the following PMU modes: Hyper, High-
Speed, Low-Speed, Standby, and Suspend. As inputs,
they can be programmed to cause System Manage-
ment Interrupts (SMIs), Non-Maskable Interrupts
The graphics controller included on the ÉlanSC400 mi-
crocontroller offers a low-cost integrated graphics solu-
tion for the mobile terminal market. Integration with the
main processor and system logic affords the advan-
Élan™SC400 and ÉlanSC410 Microcontrollers Data Sheet
17