Yamaha DRX-1 Service Manual page 45

3. Digital Board-1
START UP DSW
NOT OK
OK
Check Power Supplies on con. 1900
(ION should be LOW)
OK
Check that Sysclk_5505 on I819
appears earlier then Resetn_5505
is high on I202
OK
Check VDD_STi(+3V3) on I272
Check VDDA(+3V3) on I275
Check VDDA_PCM(+3V3) on I252
OK
Check EMI_PROCCLK(50MHz)
on I181
OK
Check if F201 is HIGH and I201 is LOW
Check if I208 is LOW and I209 is HIGH
OK
Check TCK (HIGH) on I247
Check TDI (HIGH) on I248
Check TMS (HIGH) on I249
Check TRST (LOW) on I250
OK
Check if service pin is LOW on testpoint I207
OK
Check VDD_MEM(+3V3) on I306
Check VDD_MEM1(+3V3) on I310
OK
Check VCC3_VSM(+3V3) on I100
Check VCC3_VSM_MEM(+3V3) on I141
OK
Check LOW pulses on EMI_CE3n
on pin 126 of IC 7202
OK
Check activity on EMI_CE3n(pin1 of IC 7305)
Check activity on ROMH_CEn(pin6 of IC 7305)
Check activity on EMI_OEn(pin29 of IC 7301)
OK
Check if FLASH_OEn is LOW on I245
Check if EMI_RWn is HIGH(pin133 of IC7202)
OK
Check for short circuits or open circuits on the
IC pins which are connected to the EMI-bus
OK
START UP DSW
OK
- Check connection to PSU
NOK
- Check Power Supply
- Check IC 7202
NOK
- Check IC 7916-C
- Check IC 7801
- Check IC 7202
NOK
- Check R 3266
- Check L 5200, 5201 and 5202
NOK
- Check IC 7100
- Check IC 7202
NOK
- Check L 5200
NOK
- Check IC 7202
NOK
- Check Jumper 4206
- Check L 5300
NOK
- Check L 5302
- Check L 5100
NOK
- Check L 5101
- Check IC 7202
NOK
- Check IC 7305
- Check IC 7305
NOK
- Check IC 7301
- Check IC 7202
- Check IC 7202
NOK
- Check IC 7302 and IC 7304
- Check IC 7100
Fig. 4
DRX-1
45