VRS51C1100-40-Q Cypress Semiconductor, VRS51C1100-40-Q Datasheet - Page 18

• Manufacturer Part Number: VRS51C1100-40-Q
• Description: 8-bit Microcontrollers - MCU 128K+1K 40MHz 5V
• Manufacturer: Cypress Semiconductor

Specifications of VRS51C1100-40-Q

• Product Category: 8-bit Microcontrollers - MCU
• Core: 8051
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 40 MHz
• Program Memory Size: 64 KB
• Data Ram Size: 1 KB
• Operating Supply Voltage: 4.5 V to 5.5 V
• Package / Case: QFP-44
• Mounting Style: SMD/SMT
• Data Rom Size: 128 B
• Interface Type: UART
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Number Of Programmable I/os: 36
• Number Of Timers: 3
• Program Memory Type: Flash
• Factory Pack Quantity: 96
• Supply Voltage - Max: 5.5 V
• Supply Voltage - Min: 4.5 V

I/O Ports Driving Capability
The maximum allowable continuous current that the
device can sink on an I/O port is described in the
following table:
Maximum sink current on one given I/O
Maximum total sink current for P0
Maximum total sink current for P1, 2, 3
Maximum total sink current on all I/O
It is not recommended to exceed the sink currents
outlined in the above table. Doing so will likely make
the
specifications and affect device reliability.
The VRS51C1100 I/O ports are not designed to source
current.
VRS51C1100 Timers
The VRS51C1100 includes three 16-bit timers: Timer
0, Timer 1 and Timer 2.
The Timers can operate in two modes:
When operating in event counting mode, the counter is
incremented each time an external event, such as a
transition in the logical state of the timer input (T0, T1,
T2 input), is detected. When operating in timer mode,
the counter is incremented by the microcontroller’s
system clock (Fosc/12) or by a divided version of it.
Timer 0 and Timer 1
Timers 0 and 1 have four modes of operation. These
modes allow the user to change the size of the
counting register or to authorize an automatic reload
when provided with a specific value. Timer 1 can also
be used as a baud rate generator to generate
communication frequencies for the serial interface.
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VRS51C1100
o
o
low-level
Event counting mode
Timer mode
output
voltage
exceed
10mA
26mA
15mA
71mA
device
Timers 1 and 0 are configured by the TMOD and
TCON registers.
T
The table below summarizes the four modes of
operation of timers 0 and 1. The timer operating mode
is selected by bits T1M1/T1M0 and T0M1/T0M0 of the
TMOD register.
T
ABLE
ABLE
5
4
3
2
1
0
Bit
7
6
M1 M0
0
0
1
1
GATE1
7
24: T
25: T
T1M1
T1M0
GATE0
C/T0
T0M1
T0M0
Mnemonic
GATE1
C/T1
0
1
0
1
IMER
IMER
C/T1
6
/C
M
ODE
OUNTER
Mode
Mode 0
Mode 1
Mode 2
Mode 3
C
ONTROL
T1M1
M
5
Description
1: Enables external gate control (pin INT1 for
Counter 1). When INT1 is high, and TRx bit is
set (see TCON register), a counter is
incremented every falling edge on the T1IN
input pin.
Selects timer or counter operation (Timer 1).
1 = A counter operation is performed
0 = The corresponding register will function
as a timer.
Selects the operating mode of
Timer/Counter 1
If set, enables external gate control (pin INT0
for Counter 0). When INT0 is high, and TRx
bit is set (see TCON register), a counter is
incremented every falling edge on the T0IN
input pin.
Selects timer or counter operation (Timer 0).
1 = A counter operation is performed
0 = The corresponding register will function
as a timer.
Selects the operating mode of
Timer/Counter 0.
ODE
R
D
Function
13-bit Counter
16-bit Counter
8-bit auto-reload Counter/Timer. The reload
value is kept in TH0 or TH1, while TL0 or TL1
is incremented every machine cycle. When TLx
overflows, the value of THx is copied to TLx.
If Timer 1 M1 and M0 bits are set to 1, Timer 1
stops.
EGISTER
ESCRIPTION
T1M0
4
(TMOD) – SFR 89
S
UMMARY
GATE0
3
C/T0
H
2
page 18 of 50
T0M1
1
T0M0
0