Yamaha n8 Service Manual page 127

Check that levels at each control line (SDA, SCL) between the I
I 2 C
DM-A circuit board (n8)/DM-B circuit board (n12): IC115
SDA 19 pin
SCL 18 pin
Turn on the power while simultaneously holding down the [
Or, turn on the power while simultaneously holding down the [PREV] key and [MONITOR REMOTE: REC BUS] key and the
program upgrade mode will start.
2
C and E-BUS micon are moving.
E-BUS
PN-A circuit board (n8)/PN-B circuit board (n12): IC100,IC200
PNSB circuit board (n12 only): IC1
13 pin
14 pin
A I
] (STOP) key and [ ] key and the service test program will start.
n8/n12
127