AT91RM9200-QI-002 Atmel, AT91RM9200-QI-002 Datasheet - Page 417

• Manufacturer Part Number: AT91RM9200-QI-002
• Description: IC ARM9 MCU 208 PQFP
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91RM9200-QI-002

• Core Processor: ARM9
• Core Size: 16/32-Bit
• Speed: 180MHz
• Connectivity: EBI/EMI, Ethernet, I²C, MMC, SPI, SSC, UART/USART, USB
• Peripherals: POR
• Number Of I /o: 122
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: ROM
• Ram Size: 48K x 8
• Voltage - Supply (vcc/vdd): 1.65 V ~ 1.95 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 208-MQFP, 208-PQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -

30.6.1.3
Table 30-3.
Table 30-4.
Table 30-5.
1768I–ATARM–09-Jul-09
DI field
Di (decimal)
FI field
Fi (decimal
Fi/Di
16
1
2
4
8
Baud Rate in ISO 7816 Mode
23.25
46.5
Binary and Decimal Values for F
Possible Values for the Fi/Di Ratio
372
372
186
Binary and Decimal Values for D
0000
93
372
0001
1
0001
139.5
69.75
34.87
372
558
558
279
In synchronous mode, if the external clock is selected (USCLKS = 3), the clock is provided
directly by the signal on the USART SCK pin. No division is active. The value written in
US_BRGR has no effect. The external clock frequency must be at least 4.5 times lower than the
system clock.
When either the external clock SCK or the internal clock divided (MCK/DIV) is selected, the
value programmed in CD must be even if the user has to ensure a 50:50 mark/space ratio on the
SCK pin. If the internal clock MCK is selected, the Baud Rate Generator ensures a 50:50 duty
cycle on the SCK pin, even if the value programmed in CD is odd.
The ISO7816 specification defines the bit rate with the following formula:
where:
Di is a binary value encoded on a 4-bit field, named DI, as represented in
Fi is a binary value encoded on a 4-bit field, named FI, as represented in
Table 30-5
baud rate clock.
• B is the bit rate
• Di is the bit-rate adjustment factor
• Fi is the clock frequency division factor
• f is the ISO7816 clock frequency (Hz)
BaudRate
0010
0010
558
2
46.5
774
744
372
186
93
shows the resulting Fi/Di Ratio, which is the ratio between the ISO7816 clock and the
B
=
0011
=
744
SelectedClock
------------------------------------- -
Di
----- -
Fi
139.5
69.75
1116
1116
558
279
0011
×
4
CD
f
0100
1116
1488
1488
744
372
186
93
0100
0101
1488
8
232.5
116.2
1806
1860
930
465
0110
1860
0101
16
512
512
256
128
64
32
1001
512
0110
768
768
384
192
96
48
32
1010
768
1024
1024
512
256
128
64
AT91RM9200
1011
1024
1000
Table
12
Table
1536
1536
30-4.
768
384
192
30-3.
1100
1536
96
1001
20
1101
2048
2048
2048
1024
512
256
128
417