Data Sheet

Bluegiga Technologies Oy
Page 30 of 52
The primary I
2
C interface (I
2
C 0, pins 40 and 41) is also connected to the module’s Real Time Clock (RTC)
chip and thus some additional restrictions for the communication apply. The processor is always the master.
The standard 2K pull-ups are located on APx4. Do not place additional pull-ups on I
2
C 0.
One I
2
C slave address (1010001X) on I
2
C 0 is reserved for the Real Time Clock PCF8563T on the APx4:
 Read: 0xA3 (10100011)
 Write: 0xA2 (10100010)
The secondary I
2
C (I
2
C 1) is available on pins 148 and 149 and can be used freely in either master or slave
mode. By default it is configured to provide the Debug UART. I
2
C 1 does not have built-in pull-ups.
For more details about I
2
C, please refer to the i.MX28 Applications Processor Reference Manual, chapter 27.
6.4 PWM outputs
Pin#
Default function
PWM function
Additional function
Net name
42
LCD Backlight (PWM4)
PWM4
PWM4
43
Status led (PWM3)
PWM3
PWM3
148
Debug UART TX
PWM0
I
2
C 1 bus data
PWM0/I2C1_SDA
149
Debug UART RX
PWM1
I
2
C 1 bus clock
PWM1/I2C1_SCL
83
MCLK
PWM3
UART4 CTS
SAIF0_MCLK
84
Data line 1
PWM7
SAIF1_SDATA0
85
Data line 0
PWM6
UART 4 TX
SAIF0_SDATA0
86
Bit clock
PWM5
UART4 RX
SAIF0_BITCLK
87
Left/Right clock
PWM4
UART4 RTS
SAIF0_LRCLK
Table 36: PWM outputs
The module has up to seven Pulse Width Modulator outputs available. Independent output control of each
phase allows 0, 1 or high-impedance to be independently selected for the active and inactive phases.
Two dedicated PWM outputs are at pins 42 and 43, and are typically used for the LCD’s backlight and as a
status led, respectively. The same PWM outputs are available also on pins 83 and 87.
The Debug UART on pins 148 and 149 can be disabled and used for two independent PWM outputs instead.
For more details about PWM, please refer to the i.MX28 Applications Processor Reference Manual, chapter
28.