ADE5166_08 AD [Analog Devices], ADE5166_08 Datasheet - Page 109

• Manufacturer Part Number: ADE5166_08
• Description: Single-Phase Energy Measurement IC with 8052 MCU, RTC, and LCD Driver
• Manufacturer: AD [Analog Devices]

Mode 2 (8-Bit Timer/Counter with Autoreload)
Mode 2 configures the timer register as an 8-bit counter (TL0)
with automatic reload, as shown in Figure 94. Overflow from TL0
not only sets TF0 but also reloads TL0 with the contents of TH0,
which is preset by software. The reload leaves TH0 unchanged.
Mode 3 (Two 8-Bit Timer/Counters)
Mode 3 has different effects on Timer 0 and Timer 1. Timer 1 in
Mode 3 simply holds its count. The effect is the same as setting
TR1 = 0. Timer 0 in Mode 3 establishes TL0 and TH0 as two
separate counters. This configuration is shown in Figure 95.
TL0 uses the Timer 0 control bits, C/ T0 , Gate0 (see
TR0, TF0 (see
a timer function (counting machine cycles) and takes over the
use of TR1 and TF1 from Timer 1. Therefore, TH0 controls the
Timer 1 interrupt. Mode 3 is provided for applications requiring
an extra 8-bit timer or counter.
When Timer 0 is in Mode 3, Timer 1 can be turned on and off
by switching it out of and into its own Mode 3, or it can be used
by the serial interface as a baud rate generator. In fact, Timer 1
can be used in any application not requiring an interrupt from
Timer 1 itself.
P0.6/T0
f
GATE
CORE
f
INT0
CORE
P0.6/T0
f
CORE
GATE
INT
TR1
/12
0
TRO
TR0
Table 113
C/T0 = 0
C/T0 = 1
Figure 94. Timer/Counter 0, Mode 2
Figure 95. Timer/Counter 0, Mode 3
C/T0 = 0
C/T0 = 1
), and the
CORE
CLK/12
CONTROL
CONTROL
RELOAD
(8 BITS)
(8 BITS)
(8 BITS)
INT0 pin. TH0 is locked into
TH0
(8 BITS)
TL0
TH0
TL0
TF1
TF0
TF0
INTERRUPT
INTERRUPT
Table 112
INTERRUPT
Rev. 0 | Page 109 of 148
),
TIMER 2
Timer/Counter 2 Data Registers
Timer/Counter 2 also has two pairs of 8-bit data registers asso-
ciated with it: Timer 2 high byte SFR (TH2, Address 0xCD),
Timer 2 low byte SFR (TL2, Address 0xCC), Timer 2 reload/
capture high byte SFR (RCAP2H, Address 0xCB), and Timer 2
reload/capture low byte SFR (RCAP2L, Address 0xCA). These
are used both as timer data registers and as timer capture/reload
registers (see Table 119 to Table 122).
Timer/Counter 2 Operating Modes
The following sections describe the operating modes for
Timer/Counter 2. The operating modes are selected by bits in
the Timer/Counter 2 control SFR (T2CON, Address 0xC8),
as shown in Table 114 and Table 123.
Table 123. T2CON Operating Modes
RCLK or TCLK
0
0
1
X
16-Bit Autoreload Mode
The 16-bit autoreload mode has two options that are selected by
EXEN2 (Bit 3) in the Timer/Counter 2 control SFR (T2CON,
Address 0xC8). If EXEN2 = 0 when Timer 2 rolls over, it not only
sets TF2 but also causes the Timer 2 SFRs to be reloaded with the
16-bit value in both the Timer 2 reload/capture high byte SFR
(RCAP2H, Address 0xCB) and Timer 2 reload/capture low byte
SFR (RCAP2L, Address 0xCA) registers, which are preset by
software. If EXEN2 = 1, Timer 2 performs the same events as
when EXEN2 = 0 but adds a 1-to-0 transition at the external input
pin, T2EX, which triggers the 16-bit reload and sets EXF2.
Autoreload mode is shown in Figure 96.
16-Bit Capture Mode
The 16-bit capture mode has two options that are selected by
EXEN2 (Bit 3) in the Timer/Counter 2 control SFR (T2CON,
Address 0xC8). If EXEN2 = 0, Timer 2 is a 16-bit timer or counter
that, upon overflowing, sets the Timer 2 overflow bit (TF2, Bit 7).
This bit can be used to generate an interrupt. If EXEN2 = 1, then
Timer 2 performs the same events as when EXEN2 = 0, but it
adds a l-to-0 transition on the T2E external input, causing the
current value in the Timer 2 SFRs, TL2 (Address 0xCC) and TH2
(Address 0xCD) to be captured into the RCAP2L (Address 0xCA)
and RCAP2H (Address 0xCB) SFRs, respectively. In addition, the
transition at T2EX causes the EXF2 bit (Bit 6) in the T2CON SFR
(Address 0xC8) to be set, and EXF2, like TF2, can generate an
interrupt. Capture mode is shown in Figure 97. The baud rate
generator mode is selected by RCLK = 1 and/or TCLK = 1.
CAP2
0
1
X
X
TR2
1
1
1
0
ADE5166/ADE5169
Mode
16-bit autoreload
16-bit capture
Baud rate
Off