Beck IPC SC123 - SC1 X3 System Start-up Configuration; Address Pin Configuration

IPC@CHIP SC123/SC143
Hardware Manual V1.06 [18.02.2010]
©2000-2008 BECK IPC GmbH Page 22
5 System Start-up Configuration
This chapter describes configurations for functions that are used, before any user software runs.
5.1 PIO Pins
During and after reset, all PIO pins are set to PIO as inputs with pull-ups by default.
5.2 Address Pins
A hardware design would apply pull-up or pull-down resistors on the address lines to select the desired options.
During reset, the CPU does not drive these address lines, allowing the resistors to pull the lines to their
configuration state. The CPU grabs a snapshot of the line states and stores them. After leaving the reset state,
the CPU will drive the address lines, overriding the resistors. The following table summarizes the available
options.
Ball Pin Name
External
Description
A[20]
Watchdog Enable
internal pull-up
pull-up
Enables the internal watchdog on reset (default), strongly
recommended.
pull-down
Disables the watchdog on reset. This can be useful for testing and
debugging.
A[18]
SPI enable
1
internal pull-down
pull-down
enables serial port 3 (COM3, default)
pull-up
enables SPI signals
A[15]
LEDENC
internal pull-up
pull-up
Enables LED[0..3] pins to connect to 2 bi-colour LEDs (default).
pull-down
Enables LED[0..3] pins to connect to 4 mono-colour LEDs.
e. g. see chapter 11.4
A[12]
Chip Select Byte Enable
internal pull-up
pull-up
Enables WRH# to act as WRH# (default).
Enables WRL# to act as WRL# (default).
pull-down
Enables WRH# to act as BHE#. e.g. chapter 11.3.
enables WRL# to act as A0.
BHE
A0
Type
0
0
Word Transfer
0
1
High Byte Transfer
1
0
Low Byte Transfer
1
1
Reserved
A[10]
Select Bootloader Interface
internal pull-down
pull-down
bootloader is active on COM0 (EXT, default)
pull-up
bootloader is active on COM1 (COM)
A[22, 21, 14, 13]
pull-up
2
Reserved
These pins are reserved for production only. Be sure that these
pins are not driven by any other connected active or passive
device.
internal pull-up
A[19, 17, 16, 11,
9..1]
pull-down
2
internal pull-down
1
can also configured by software through RTOS API
2
these resistors are only necessary, if any device is connected to these pins
The external resistors should have 10 K .