C8051F021 Silicon Laboratories Inc, C8051F021 Datasheet - Page 166

• Manufacturer Part Number: C8051F021
• Description: IC 8051 MCU 64K FLASH 64TQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F02xr

Specifications of C8051F021

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: EBI/EMI, SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 32
• Program Memory Size: 64KB (64K x 8)
• Program Memory Type: FLASH
• Ram Size: 4.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 8x8b, 8x12b; D/A 2x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP, 64-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

C8051F020/1/2/3
17.1.7. External Memory Interface Pin Assignments
If the External Memory Interface (EMIF) is enabled on the Low ports (Ports 0 through 3), EMIFLE (XBR2.1) should
be set to a logic 1 so that the Crossbar will not assign peripherals to P0.7 (/WR), P0.6 (/RD), and if the External Mem-
ory Interface is in Multiplexed mode, P0.5 (ALE). Figure 17.4 shows an example Crossbar Decode Table with
EMIFLE=1 and the EMIF in Multiplexed mode. Figure 17.5 shows an example Crossbar Decode Table with
EMIFLE=1 and the EMIF in Non-multiplexed mode.
If the External Memory Interface is enabled on the Low ports and an off-chip MOVX operation occurs, the External
Memory Interface will control the output states of the affected Port pins during the execution phase of the MOVX
instruction, regardless of the settings of the Crossbar registers or the Port Data registers. The output configuration of
the Port pins is not affected by the EMIF operation, except that Read operations will explicitly disable the output
drivers on the Data Bus. See
XRAM” on page 145
166
TX0
RX0
SCK
MISO
MOSI
NSS
SDA
SCL
TX1
RX1
CEX0
CEX1
CEX2
CEX3
CEX4
ECI
CP0
CP1
T0
/INT0
T1
/INT1
T2
T2EX
T4
T4EX
/SYSCLK
CNVSTR
PIN I/O 0
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3
P0
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EMIFLE = 1; EMIF in Multiplexed Mode; P1MDIN = 0xFF)
4
5
for more information about the External Memory Interface.
6
7
Figure 17.4. Priority Crossbar Decode Table
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0
AIN1 Inputs/Non-muxed Addr H Muxed Addr H/Non-muxed Addr L
Section “16. EXTERNAL DATA MEMORY INTERFACE AND ON-CHIP
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2
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3
P1
4
5
6
7
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0
Rev. 1.4
1
2
3
P2
4
5
6
7
0
Muxed Data/Non-muxed Data
1
2
3
P3
4
5
6
7
Crossbar Register Bits
UART0EN:
UART1EN:
SMB0EN:
PCA0ME:
SYSCKE: XBR1.7
CNVSTE: XBR2.0
SPI0EN:
T2EXE: XBR1.6
T4EXE: XBR2.4
ECI0E: XBR0.6
INT0E: XBR1.2
INT1E: XBR1.4
CP0E: XBR0.7
CP1E: XBR1.0
T0E: XBR1.1
T1E: XBR1.3
T2E: XBR1.5
T4E: XBR2.3
XBR0.2
XBR0.1
XBR0.0
XBR2.2
XBR0.[5:3]