PCA84C922AP PHILIPS [NXP Semiconductors], PCA84C922AP Datasheet - Page 22

• Manufacturer Part Number: PCA84C922AP
• Description: Microcontrollers for universal infrared remote transmitter applications
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
11 INTERRUPTS
The PCA84C92X has three interrupt sources:
1. External keypad wake-up and T0/INT pin; vector
2. Hardware Modulator; vector address 05H.
3. Internal Timer/counter (T1); vector address 07H.
11.1
This interrupt will wake-up the CPU from the Stop mode
when a HIGH-to-LOW transition occurs on any Port 1 pin
or the T0/INT pin (see Fig.1); normal program execution
will continue after a 1866 clock cycle delay.
If this interrupt was enabled (by using the ‘EN I’ instruction)
before the Stop mode was entered, then when the CPU is
woken-up, the instruction that follows the STOP instruction
will be executed before diverting to the interrupt routine at
vector address 03H. However, if the interrupt was not
enabled before the Stop mode was entered, then when the
CPU is woken-up the instruction that follows the STOP
instruction will be executed.
11.2
When a complete pulse train has been transmitted by the
Hardware Modulator, it generates an interrupt to the CPU
by asserting EXDI and the operation of the Hardware
Modulator is halted. This derivative interrupt is shared with
the SIO interrupt of the PCF84CXXXA family; both use
vector address 05H. The Hardware Modulator interrupt is
enabled using the instruction ‘EN SI’ and is disabled using
the ‘DIS SI’ instruction.
11.3
The Timer/counter and its interrupt are common to other
members of the PCF84CXXXA family; all operate in a
similar manner. The Timer/counter interrupt is enabled
using the instruction ‘EN TCNT1’ and is disabled using the
‘DIS TCNT1’ instruction.
1997 Oct 22
Microcontrollers for universal infrared
remote transmitter applications
address 03H.
External keypad wake-up and T0/INT pin
interrupt
Hardware Modulator interrupt
Internal Timer/counter (T1) interrupt
22
12 DERIVATIVE REGISTERS
The Derivative Registers residing at addresses 00 to 04H
are dedicated to the Hardware Modulator; these registers
are also common to the PCA84CX22 range of
microcontrollers. The Derivative Registers residing at
addresses 05 to 08H are used for accessing the Coding
Table. The Derivative Registers memory map is shown in
Table 9.
When the Coding Table is accessed data will be read from
Derivative Port 5 terminal (address 05H) regardless of
whether the internal or external Coding table was
addressed. Details of accessing the internal or external
Coding Tables are given in Section 8. As Derivative Port 6
latch is also connected to the High byte address of the
internal Coding Table, writing data to Derivative Port 6
latch (address 08H) also addresses the Coding Table.
PCA84C922; PCA84C923
Product specification