EM78815
8-Bit Microcontroller
APPENDIX
A Application Note
1. In targeting interrupt and program run to address 0x0008, ACC, R3 (Status), R5
(Program Page) and R4 (6, 7) will be automatically saved and R3 (6, 7) R register
page will be set to Page 0, and reload after the instruction “RETI”.
2. 0V reference voltage will power down when both RD Page 2 Bit 7 (DAREF) and
RA Page 2 Bit 7 (CMPEN) are cleared to 0.
3. Before using Keytone function, set Port 76 as output type.
4. For accessing data ROM, EM78P815 (OTP) can work at 10.74MHz, but note that
only ROM type EM78815 can work at 5.3MHz.
5. While switching the main clock (regardless of high freq to low freq or vice versa),
adding 6 instructions delay (NOP) is required.
6. Do not switch the MCU operation mode from normal mode to sleep mode directly.
Before going into sleep mode, switch the MCU to green mode first.
7. Always keep RA Page 0 Bit 7 = 0, otherwise, unexpected error will occur.
Product Specification (V2.4) 08.01.2004
(This specification is subject to change without further notice)
75
ELAN [ ELAN MICROELECTRONICS CORP ]
