Freescale Semiconductor M9328MX21ADSE user manual USB On-The-Go Interface, Uart and IrDA

Configuration and Operation

the entire 64 MB address space allowed for CSD0, but the Burst Flash occupies only 32 MB of the 64 MB space available to CS0, so it appears in two different ranges of addresses. CS1 covers 16 MB allowing many repetitions of the memory mapped peripherals.

Table 2-4. M9328MX21ADSE Memory Map

Peripheral	Chip Select				Address Range (HEX)	Act Mem Size
SDRAM					0xC000_0000 to 0xC3FF_FFFF	64 MB
		CSD0
Burst FLASH					0xC800 0000 to 0xC9FF_FFFF	32 MB
				CS0
Ethernet Controller					0xCC00 0000 to 0xCC00_000F*	16 BYTES
				CS1
External DUART					0xCC20 0000 to 0xCC20_000F*	16 BYTES
			CS1
Read CPU and					Read 0xCC40_0000*
				CS1		2 BYTES
Base board versions					D7-D0 = CPU, D15-D8 = Base board
					Write to 0xCC80_0000* (Output)	2 BYTES
Memory Mapped I/O				CS1
					Read 0xCC80_0000* (Input)	2 BYTES
				CS1

* For I/O operations only D15 - D0 are used

2.3.4USB On-The-Go Interface

The i.MX21 USB OTG Device Module interfaces with a Phillips ISP1301BS USB transceiver connected to P4, a mini AB USB connector. The interface can function as either a USB host or USB device. The interface includes a Maxim MAX3355EUD+ USB power supply chip which can provide power on the USB bus in host mode. This power supply chip is enabled by the USB_PWR signal. For details on the operation of the USB interface, refer to the i.MX21 data sheet. Figure 2-6shows the USB interface connection.

i.MX21

USB_PWR

ISP1301BS

D-

D+

VBUS

ID

VBUS

IDIN

IDOUT

SHDN

MAX3355EUD+

P4

USB MINI AB

USB Device

Figure 2-6. USB OTG Interface

2.3.5UART and IrDA

Figure 2-7shows how to connect the UART and IrDA circuits.

M9328MX21ADSE User’s Manual, Rev. A

2-6

Freescale Semiconductor