T89C5121-ICUIL Atmel, T89C5121-ICUIL Datasheet - Page 75

• Manufacturer Part Number: T89C5121-ICUIL
• Description: IC 8051 MCU W/SMART CARD 24SSOP
• Manufacturer: Atmel
• Series: 89Cr

Specifications of T89C5121-ICUIL

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SmartCard, UART/USART
• Peripherals: LED, POR, WDT
• Number Of I /o: 14
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: Flash RAM
• Eeprom Size: 16K x 8
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 2.85 V ~ 5.4 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 24-SSOP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Data Converters: -
• Other names: Q1468934; T89C5121-ICSIL; T89C5121-ICSIL

Figure 29. Timer 0/Counter x (x = 0 or 1) in Mode 1
Mode 2 (8-bit Timer 0 with
Auto-Reload)
Figure 30. Timer 0/Counter x (x = 0 or 1) in Mode 2
Mode 3 (Two 8-bit Timer 0s)
4164G–SCR–07/06
INTx#
INTx#
Tx
Tx
TMOD reg
GATEx
TMOD reg
FCLK_Periph
GATEx
FCLK_Periph
TMOD reg
C/Tx#
Mode 2 configures Timer 0 as an 8-bit Timer 0 (TL0 register) that automatically reloads
from the TH0 register (see Figure 30). TL0 overflow sets the TF0 flag in the TCON reg-
ister and reloads TL0 with the contents of TH0, which is preset by the software. When
the interrupt request is serviced, the hardware clears TF0. The reload leaves TH0
unchanged. The next reload value may be changed at any time by writing it to the TH0
register.
Mode 3 configures Timer 0 so that registers TL0 and TH0 operate as 8-bit Timer 0s (see
Figure 31). This mode is provided for applications requiring an additional 8-bit Timer 0 or
Counter. TL0 uses the Timer 0 control bits C/T0# and GATE0 in the TMOD register, and
TR0 and TF0 in the TCON register in the normal manner. TH0 is locked into a Timer 0
function (counting F
trol (TR1) bits. Thus, operation of Timer 1 is restricted when Timer 0 is in mode 3.
TCON reg
0
1
TCON reg
TRx
TRx
TMOD reg
C/Tx#
0
1
UART
) and takes over use of the Timer 1 interrupt (TF1) and run con-
(8 bits)
THx
(8 bits)
(8 bits)
THx
TLx
(8 bits)
TLx
Overflow
Overflow
TCON reg
TCON reg
TFx
TFx
A/T8xC5121
Timer 0 x
Interrupt
Request
Timer 0 x
Interrupt
Request
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