AN2131SC Cypress Semiconductor Corp, AN2131SC Datasheet - Page 69

• Manufacturer Part Number: AN2131SC
• Description: IC MCU 8051 8K RAM 24MHZ 44QFP
• Manufacturer: Cypress Semiconductor Corp
• Series: EZ-USB®r

Specifications of AN2131SC

• Applications: USB Microcontroller
• Core Processor: 8051
• Program Memory Type: ROMless
• Controller Series: AN213x
• Ram Size: 8K x 8
• Interface: I²C, USB
• Number Of I /o: 16
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 44-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 428-1306; AN2131SC

The 8051 uses the two registers shown in Figure 4-7 to conduct I
transfers data to and from the I
12CS register controls I
trol bits are START, STOP, and LASTRD. The remaining bits are status bits. Writing to a
status bit has no effect.
4.6.1 START
The 8051 sets the START bit to 1 to prepare an I
8051 load to I2DAT will generate the start condition followed by the serialized byte of
data in I2DAT. The 8051 loads data in the format shown in Figure 4-5 after setting the
START bit. The I
Figure 4-5).
4.6.2 STOP
The 8051 sets STOP=1 to terminate an I
STOP bit after completing the STOP condition. If the 8051 sets the STOP bit during a
byte transfer, the STOP condition will be generated immediately following the ACK phase
of the byte transfer. If no byte transfer is occurring when the STOP bit is set, the STOP
condition will be carried out immediately on the bus. Data should not be written to I2CS
Page 4-8
I2CS
I2DAT
4.6
START
D7
b7
b7
Control Bits
STOP
D6
b6
b6
2
C controller clears the START bit during the ACK interval (clock 9 in
2
LASTRD
C transfers and reports various status conditions. The three con-
D5
b5
b5
2
C bus by writing and reading the I2DAT register. The
I
2
Figure 4-7. FC Registers
C Control and Status
Chapter 4. EZ-USB CPU
ID1
D4
b4
b4
I
2
C bus transfer. The I
2
C Data
2
ID0
C bus transfer. If START=1, the next
D3
b3
b3
BERR
D2
b2
b2
2
C controller clears the
2
C transfers. The 8051
ACK
D1
b1
b1
EZ-USB TRM v1.9
DONE
D0
b0
b0
7FA5
7FA6