CY7C63743-PXC Cypress Semiconductor Corp, CY7C63743-PXC Datasheet - Page 24

• Manufacturer Part Number: CY7C63743-PXC
• Description: IC MCU 8K USB/PS2 LS 24DIP
• Manufacturer: Cypress Semiconductor Corp
• Series: enCoRe™r

Specifications of CY7C63743-PXC

• Applications: USB Microcontroller
• Core Processor: M8B
• Program Memory Type: OTP (8 kB)
• Controller Series: CY7C637xx
• Ram Size: 256 x 8
• Interface: PS2, USB
• Number Of I /o: 16
• Voltage - Supply: 4 V ~ 5.5 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Through Hole
• Package / Case: 24-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 428-1621

18.0
The 12-bit timer operates with a 1-µs tick, provides two inter-
rupts (128-µs and 1.024-ms) and allows the firmware to
directly time events that are up to 4 ms in duration. The lower
eight bits of the timer can be read directly by the firmware.
Reading the lower eight bits latches the upper four bits into a
temporary register. When the firmware reads the upper four
bits of the timer, it is actually reading the count stored in the
temporary register. The effect of this is to ensure a stable 12-bit
timer value can be read, even when the two reads are
separated in time.
Document #: 38-08022 Rev. *B
Read/Write
Bit Name
Reset
Bit #
Figure 18-1. Timer LSB Register (Address 0x24)
12-bit Free-running Timer
11
L3
R
7
0
D3
10
L2
R
6
0
D2
9
L1
R
5
0
D1
Timer [7:0]
8
L0
R
4
0
D0
FOR
FOR
7
R
3
0
D7
Figure 18-3. Timer Block Diagram
R
2
0
6
D6
R
1
0
5
D5
R
0
0
4
D4
3
Bit [7:0]: Timer lower eight bits
Bit [7:4]: Reserved
Bit [3:0]: Timer upper four bits
Read/Write
D3
Bit Name
Reset
Bit #
Figure 18-2. Timer MSB Register (Address 0x25)
2
D2
1
D1
7
0
-
8
0
D0
Reserved
6
0
-
5
0
-
1.024-ms interrupt
128-
1 MHz clock
To Timer Registers
4
0
-
µ
s interrupt
R
3
0
CY7C63722
CY7C63723
CY7C63743
Timer [11:8]
R
2
0
Page 24 of 49
R
1
0
R
0
0