MC9328MX21S_08 Datasheet, PDF (11/88 Pages) Freescale Semiconductor, Inc – i.MX family of microprocessors 266 MHz

Signal Descriptions
Table 2. i.MX21S Signal Descriptions (Continued)
Signal Name
UART4_CTS
SSI1_CLK
SSI1_TXD
SSI1_RXD
SSI1_FS
SYS_CLK1
SSI2_CLK
SSI2_TXD
SSI2_RXD
SSI2_FS
SYS_CLK2
SSI3_CLK
SSI3_TXD
SSI3_RXD
SSI3_FS
SAP_CLK
SAP_TXD
SAP_RXD
SAP_FS
I2C_CLK
I2C_DATA
OWIRE
PWMO
PB[10:21], PF[16]
KP_COL[7:0]
Function/Notes
Clear to Send output signal which is multiplexed with USBH1_TXDP and USBH1_RXDM.
Serial Audio Port – SSI (configurable to I²S protocol and AC97)
Serial clock signal which is output in master or input in slave
Transmit serial data
Receive serial data
Frame Sync signal which is output in master and input in slave
SSI1 master clock. Multiplexed with TOUT.
Serial clock signal which is output in master or input in slave.
Transmit serial data signal
Receive serial data
Frame Sync signal which is output in master and input in slave.
SSI2 master clock. Multiplexed with TOUT.
Serial clock signal which is output in master or input in slave. Multiplexed with SLCDC2_CLK
Transmit serial data signal which is multiplexed with SLCDC2_CS
Receive serial data which is multiplexed with SLCDC2_RS
Frame Sync signal which is output in master and input in slave. Multiplexed with SLCDC2_D0.
Serial clock signal which is output in master or input in slave.
Transmit serial data
Receive serial data
Frame Sync signal which is output in master and input in slave.
I²C
I²C Clock
I²C Data
1-Wire
1-Wire input and output signal. This signal is multiplexed with JTAG RTCK.
PWM
PWM Output. This signal is multiplexed with PC_SPKOUT of PCMCIA, as well as TOUT2 and TOUT3
of the General Purpose Timer module.
General Purpose Input/Output
Dedicated GPIO. When unused, program this signal as an input with the on-chip pull-up resistor enabled.
Keypad
Keypad Column selection signals. KP_COL[7:6] are multiplexed with UART2_CTS and UART2_TXD
respectively. Alternatively, KP_COL6 is also available on the internal factory test signal TEST_WB2. The
Function Multiplexing Control Register in the System Control chapter must be used in conjunction with
programming the GPIO multiplexing (to select the alternate signal multiplexing) to choose which signal
KP_COL6 is available.
MC9328MX21S Technical Data, Rev. 1.3
Freescale Semiconductor
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