em78p862a ELAN Microelectronics Corp, em78p862a Datasheet - Page 25

• Manufacturer Part Number: em78p862a
• Description: 8-bit Risc Type Microprocessor
• Manufacturer: ELAN Microelectronics Corp

This specification is subject to change without further notice.
6.3
An 8-bit counter is available as pre-scaler for the TCC or WDT. The pre-scaler is available
only to either the TCC or WDT at a time.
An 8-bit counter is available for TCC or WDT as determined by the status of Bit 3 (PAB) of
CONT register.
The pre-scaler ratio is described in Section 6.2.2 CONT (Control Register).
The TCC/WDT circuit diagram is shown in Fig. 9 below.
Both TCC and pre-scaler are cleared by instructions.
The pre-scaler will be cleared by the WDTC and SLEP instructions when running in WDT
mode.
However, pre-scaler will not be cleared by SLEP instruction when running in TCC mode.
TCC/WDT Pre-Scaler
16.38KHz
or RC/2
OSCSEL
WDTE
WDT
CLK(=Fosc/2)
Fig. 9 TCC WDT Block Diagram
0
0
1
1
TS
PAB
1
0
WDT Timeout
PAB
8-BIT Counter
0
8-to-1 MUX
MUX
2 Cycles
SYNC
1
8-Bit RISC Type Microprocessor
PAB
TCC Overflow
Data Bus
TCC(R1)
Interrupt
08.02.2004 (V1.0)
PSR0~PSR2
EM78862B
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