COP888CL Datasheet, PDF (16/42 Pages) Texas Instruments – COP888CL 8-Bit Microcontroller

Oscillator Circuits (Continued)
TABLE 1. Crystal Oscillator Configuration, T_A = 25˚C
R1 R2 C1
C2
CKI
Conditions
Freq
(kΩ) (MΩ) (pF) (pF)
(MHz)
0
1
30 30–36
10
V_CC = 5V
0
1
30 30–36
4
V_CC = 5.0V
0
1 200 100–150 0.455
V_CC = 5V
Control Registers
CNTRL Register (Address X'00EE)
The Timer1 (T1) and MICROWIRE/PLUS control register
contains the following bits:
SL1 & SL0 Select the MICROWIRE/PLUS clock divide
by (00 = 2, 01 = 4, 1x = 8)
IEDG
External interrupt edge polarity select
(0 = Rising edge, 1 = Falling edge)
MSEL
Selects G5 and G4 as MICROWIRE/PLUS
signals SK and SO respectively
T1C0 Timer T1 Start/Stop control in timer
modes 1 and 2
Timer T1 Underflow Interrupt Pending Flag in timer
mode 3
T1C1 Timer T1 mode control bit
T1C2 Timer T1 mode control bit
T1C3 Timer T1 mode control bit
T1C3 T1C2 T1C1 T1C0 MSEL IEDG SL1 SL0
Bit 7
Bit 0
PSW Register (Address X'00EF)
The PSW register contains the following select bits:
GIE
Global interrupt enable (enables interrupts)
EXEN Enable external interrupt
BUSY MICROWIRE/PLUS busy shifting flag
EXPND External interrupt pending
T1ENA Timer T1 Interrupt Enable for Timer Underflow
or T1A Input capture edge
T1PNDA Timer T1 Interrupt Pending Flag (Autoreload
RA in mode 1, T1 Underflow in Mode 2, T1A
capture edge in mode 3)
C
Carry Flag
HC
Half Carry Flag
HC C T1PNDA T1ENA EXPND BUSY EXEN GIE
Bit 7
Bit
0
The Half-Carry bit is also affected by all the instructions that
affect the Carry flag. The SC (Set Carry) and RC (Reset
Carry) instructions will respectively set or clear both the carry
flags. In addition to the SC and RC instructions, ADC, SUBC,
RRC and RLC instructions affect the carry and Half Carry
flags.
TABLE 2. RC Oscillator Configuration, T_A = 25˚C
R
C CKI Freq Instr. Cycle Conditions
(kΩ) (pF)
(MHz)
(µs)
3.3 82 2.2 to 2.7
5.6 100 1.1 to 1.3
6.8 100 0.9 to 1.1
3.7 to 4.6
7.4 to 9.0
8.8 to 10.8
V_CC = 5V
V_CC = 5V
V_CC = 5V
Note 23: 3k ≤ R ≤ 200k, 50 pF ≤ C ≤ 200 pF
ICNTRL Register (Address X'00E8)
The ICNTRL register contains the following bits:
T1ENB Timer T1 Interrupt Enable for T1B Input capture
edge
T1PNDB Timer T1 Interrupt Pending Flag for T1B cap-
ture edge
µWEN Enable MICROWIRE/PLUS interrupt
µWPND MICROWIRE/PLUS interrupt pending
T0EN Timer T0 Interrupt Enable (Bit 12 toggle)
T0PND Timer T0 Interrupt pending
LPEN
L Port Interrupt Enable (Multi-Input Wakeup/
Interrupt)
Bit 7 could be used as a flag
Unused LPENT0PND T0EN µWPND µWENT1PNDB T1ENB
Bit 7
Bit 0
T2CNTRL Register (Address X'00C6)
The T2CNTRL register contains the following bits:
T2ENB Timer T2 Interrupt Enable for T2B Input capture
edge
T2PNDB Timer T2 Interrupt Pending Flag for T2B cap-
ture edge
T2ENA Timer T2 Interrupt Enable for Timer Underflow
or T2A Input capture edge
T2PNDA Timer T2 Interrupt Pending Flag (Autoreload
RA in mode 1, T2 Underflow in mode 2, T2A
capture edge in mode 3)
T2C0
Timer T2 Start/Stop control in timer modes 1
and 2 Timer T2 Underflow Interrupt Pending
Flag in timer mode 3
T2C1 Timer T2 mode control bit
T2C2 Timer T2 mode control bit
T2C3 Timer T2 mode control bit
T2C3 T2C2 T2C1 T2C0 T2PNDA T2ENA T2PNDB T2ENB
Bit
Bit 0
7
15
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