Service Manual - AMS Neve

SynchroNet ES/2 Service Manual
CIRCUIT DESCRIPTION
The COMMS chip select lines are generated from the address lines EA11 through to EA15 and
gated with the !EVMA enable signal. Figure 3 shows this in the form of an address map.
For more information see the information on FPGA decode under Kernel and Machine ROMs
above.
The COMMS chip select output signals are:
!EROM - 32K
U4 on the program module, a 27C256 EPROM.
!ERAM - 8K
U42, a 6264 non battery backed up RAM.
!SIO - 4 locations
U44, a Z84C42 serial interface chip.
!ECTC - 8 locations U43, a 68B40 counter timer chip.
!EFIFO1 - 1 locations U41, read from the KERNEL interface.
!EFIFO2 - 1 locations U42, write to the KERNEL interface.
!COMSEL - 2 locations U39, read FIFO flags and write to comms LED latch
KERNEL decoding
The KERNEL chip select lines are generated from the address lines BA7 through to BA15 and are
either gated with the !BVMA or the E signal, depending on the timing requirement of the device
being selected. Figure 4 shows this in the form of an address map. For more information see the
information on FPGA DECODE in chapter 2. The KERNEL chip select output signals are :
!ROM - 8x16K
U2 on the program module, a 27C1001 EPROM.
!MACH - 8x16K
U3 on the program module, a 27C1001 EPROM.
!BBRAM - 16K
U53, a 62256 battery backed up RAM - 50% used.
!SCOM - 4 locations U49, a Z84C42 serial interface chip.
!CTC1 - 8 locations U54, a 68B40 counter timer chip.
!CTC2 - 8 locations U55, a 68B40 counter timer chip.
!CTC3 - 8 locations U56, a 68B40 counter timer chip.
!BFIFO1 - 1 location U42, read from the COMMS interface.
!BFIFO2 - 1 location U41, write to the COMMS interface.
!ICU1 - 2 locations Master interrupt control unit.
!ICU2 - 2 locations Slave interrupt control unit.
!INTA - 1 location
IRQ source clear.
!VITC - 16 locations VITC expansion slot.
!LTCR - 8 locations U37, LTC reader chip.
!BHOLE - 256 locations BLACK HOLE expansion slot.
!TALLY - 1 location U21, Tally buffer.
!CMD - 1 location
U25, Command latch
!LED - 1 location
U31, LED latch
!DAC - 2 locations
U9, DC servo DAC.
!SUPPORT - 10 locations U39, control ports.
!SPLIT - 6 locations U38, control ports.
!MCN - 4 locations U36, control ports.
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