t89c51rd2-slscl ATMEL Corporation, t89c51rd2-slscl Datasheet - Page 12

• Manufacturer Part Number: t89c51rd2-slscl
• Description: 0 To 40 Mhz Flash Programmable 8-bit Microcontroller
• Manufacturer: ATMEL Corporation

12
T89C51RD2
Reset Value = X000 0000b
Not bit addressable
Number
Bit
2
1
0
Mnemonic Description
T1X2
T0X2
Bit
X2
Timer1 clock (This control bit is validated when the CPU clock X2 is set; when X2
is low, this bit has no effect)
Clear to select 6 clock periods per peripheral clock cycle.
Set to select 12 clock periods per peripheral clock cycle
Timer0 clock (This control bit is validated when the CPU clock X2 is set; when X2
is low, this bit has no effect)
Clear to select 6 clock periods per peripheral clock cycle.
Set to select 12 clock periods per peripheral clock cycle
CPU clock
Clear to select 12 clock periods per machine cycle (STD mode) for CPU and all the
peripherals.
Set to select 6clock periods per machine cycle (X2 mode) and to enable the
individual peripherals "X2" bits.
4243G–8051–05/03