Freescale Semiconductor M9328MX21ADSE User Manual

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Configuration and Operation
M9328MX21ADSE User’s Manual, Rev. A
2-2
Freescale Semiconductor
2.2.1
Peripheral Selection Switch (S1)
S1 is a DIP switch that consists of eight slide switches. Seven of the switches enable and disable software 
control of the UART transceivers, the IrDA buffers, the Nexus buffer, the touch panel controls, and the 
buzzer. One switch selects JTAG operation mode.
Figure 2-1 shows an example configuration. The switches are set so that the UART1 transceiver and the 
IrDA module are forced enabled; the UART4 transceiver can be enabled by software; and the NEXUS 
buffer and buzzer are disabled. In addition, ARM mode JTAG is selected and the LCD touch control 
signals are enabled. 
Modem Control Enable 
Jumpers
(on Base board)
J3, DTR
J4, DSR
J5, CD
J6, RI
The specified RS-232 control signal of P2 connects to the specified 
I/O signal.
J3 - DTR (pin 4) is controlled by SD2_D0 (output)
J4 - DSR (pin 6) can be read on SD2_D1 (input)
J5 - CD (pin 1) can be read on SD2-D2 (input)
J6 - RI (pin 9) can be read on SD2-D3 (input)
The specified RS-232 control signal of P2 is not connected to any I/O 
signal and cannot be controlled or read.
J3 - DTR is forced active (positive), SD2_D0 is unused
J4 - DSR cannot be read, SD2_D1 is unused
J5 - CD cannot be read, SD2_D2 is unused
J6 - RI cannot be read, SD2_D3 is unused
Table 2-2.  S1 Switch Settings
Switch Name
Setting
Effect
S1-1, UART1_ON
ON
Forces the UART1 transceiver to be enabled.
OFF
UART1_EN_B bit controls the UART1 transceiver
S1-2, UART4_ON
ON
Forces the UART4 transceiver to be enabled.
OFF
UART4_EN_B bit controls the UART4 transceiver
S1-3, IrDA_ON
ON
Forces the IrDA module buffers to be enabled.
OFF
IrDA_EN bit controls the IrDA buffers
S1-4, NEXUS_EN
ON
Internal test only.
OFF
Set to OFF for debugging purposes.
S1-5, JTAG _CTRL
ON
Internal test only.
OFF
ARM Multi-ICE mode selected after TRST.
S1-6, TONE_OUT
ON
The buzzer is controlled by the PWMO output.
OFF
PWMO is disconnected from the buzzer circuit.
S1-7, PEN_CS_B
 ON
CSPI_SS0 controls the chip enable of the Touch controller.
OFF
Disables CSPI_SS0 control of the Touch controller chip enable. 
S1-8, PEN_IRQ_B 
 ON
UART3_CTS is connected to PENIRQ_B out of the Touch controller.
OFF
UART3_CTS is not connected to PENIRQ_B out of the Touch controller.* 
*PENIRQ_B is not connected to anything.
Table 2-1.  Component Configuration Settings (continued)
Component
Position
Effect
1 2 3
1 2 3