
S1C60N08 TECHNICAL HARDWARE
EPSON
I-87
CHAPTER 5: SUMMARY OF NOTES
When the CPU system clock is fOSC3 (in case of S1C60A08 only)
1. When detection is done at HLMOD
After writing "1" on HLMOD, read the BLD after 0.6 second has passed. (HLMOD holds "1" for at
least 0.6 second)
2. When detection is done at BLS
Before writing "1" on BLS, write "1" on HLMOD first; after at least 100 sec has lapsed after
writing "1" on BLS, write "0" on BLS and then read the BLD.
(2) BLS resides in the same bit at the same address as BLD1, and one or the other is selected by write or
read operation. This means that arithmetic operations (AND, OR, ADD, SUB and so forth) cannot be
used for BLS control.
Heavy load protection function and sub-BLD circuit
(1) It takes 100 sec from the time the BLD circuit goes ON until a stable result is obtained. For this
reason, keep the following software notes in mind:
When the CPU system clock is fOSC1
1. When detection is done at HLMOD
After writing "1" on HLMOD, read the BLD after 1 instruction has passed.
2. When detection is done at BLS
After writing "1" on BLS, write "0" after at least 100 sec has lapsed (possible with the next instruc-
tion) and then read the BLD.
When the CPU system clock is fOSC3 (in case of S1C60A08 only)
1. When detection is done at HLMOD
After writing "1" on HLMOD, read the BLD after 0.6 second has passed. (HLMOD holds "1" for at
least 0.6 second)
2. When detection is done at BLS
Before writing "1" on BLS, write "1" on HLMOD first; after at least 100 sec has lapsed after
writing "1" on BLS, write "0" on BLS and then read the BLD.
(2) BLS resides in the same bit at the same address as BLD1, and one or the other is selected by write or
read operation. This means that arithmetic operations (AND, OR, ADD, SUB and so forth) cannot be
used for BLS control.
(3) Select one of the following software processing to return to the normal mode after a heavy load has
been driven in the heavy load protection mode in the S1C60L08.
After heavy load drive is completed, return to the normal mode after at least one second has
elapsed.
After heavy load drive is completed, switch BLS ON and OFF (at least 100 sec is necessary for the
ON status) and then return to the normal mode.
The S1C60N08/60A08 returns to the normal mode after driving a heavy load without special software
processing.
(4) If the BLS is set to ON while the heavy load protection mode is in effect, keep the ON time within 10
msec.