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Seeking CommSlot I and CommSlot II technical documentation, pinouts

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Hiya, I was working on this PM before I saw you post:


You'll probably find the CSII pinout it in any of the CSII equipped series Developer Notes. I was looking at the 5400 DevNote earlier and found it. Apple calls it the PCI-Bus Communications Slot. Maybe someone has a link to that handy or to any other CSII machine DevNotes? If not, PM an addy and I can email it to you, haven't got the original title of the PDF for searching.


Looked after you posted the thread, but I didn't see CSI in theQuadra/LC 630 series DevNote though.



In a tangent in another thread, you'd mentioned wondering about RPI Zero W for CSII Networking and a general lack of SBC compatibility with PCI, which sent me right off on a search:


Article about the hack free RPi CM4 version with PCIe:



Article about hacking off the USB3 controller from a standard Raspberry Pi 4 to get at its PCIe interface:



YouBoobTube fun look at that hack:



The full-on carrier board for CM4 appears to have a slot supporting its PCIe Gen 2 x1 interface. I'll make a working assumption it can be made to communicate bidirectionally with the "PCI-Bus Communications Slot Connector." The reduced 55mm × 40mm board size of the new CM card and interconnect fits it well enough into CSII Slot card cubic and onto some magical carrier card for that slot?


That's as far as I got. It's all Greek to me, but fun finding the stuff. [:)]


edit: I see you've found the CS(I) pinout. moar:



I think I got all that into my reply in the new post, I hope it's helpful. Fab idea on slotting RPi into the PCI-Bus Communications Slot, hopefully it won't need to be jusdt a serial connection! [:)]



Edited by Trash80toHP_Mini
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Looks like it's inexpensive enough to connect PCIe to PCI.

https://www.newegg.com/riitop-model-pcetpci-pci-express-controller-card/p/17Z-0061-00016?Description=PCIe to PCI adapter&cm_re=PCIe_to PCI adapter-_-9SIA6V85DD5236-_-Product

https://www.newegg.com/p/17Z-00PR-03584?Description=PCIe to PCI adapter&cm_re=PCIe_to PCI adapter-_-9SIAKFCA219437-_-Product


I wonder if it might be as simple as a PCI edgecard to CSII Slot edgecard signal adapter riser? Bodging a CM 4 carrier to the PCIe edgecard connector topside might complete the hardware hookup for testing purposes?


If that works out, a CSII riser/CM 4 carrier might be reduced to a single card with the ASMEDIA1083 IC on board? I'd bet it could fit in the TAM.


Edited by Trash80toHP_Mini
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Just did a comparison of the PCI-Bus Communications Slot against the PCI control signal listing in the 5400 DevNote.


PCI Expansion Slot

AD [0Ð31]        Address and data, multiplexed
C/BE[0Ð3]        Bus command and byte enable signals, multiplexed
PAR        Parity; used with AD and C/BE signals
FRAME#        Cycle frame; asserted to indicate a bus transaction
TRDY#            Target ready; selected device is able to complete the current phase
IRDY#        Initiator ready; master device is able to complete the current phase
STOP#        Stop; indicates the current target device is requesting the master to stop the current transaction
DEVSEL#        Device select; indicates that the driving device has decoded its address as the target of the current access
IDSEL        Initialization device select; used during configuration
REQ#        Request; indicates to the arbiter that the asserting agent requires use of the bus
GNT#        Grant; indicates to the agent that access to the bus has been granted
CLK        Clock; rising edge provides timing for all transactions
RST#        Reset; used to bring registers and signals to a known state
INTD#        Interrupt request pins; wired together on each slot
LOCK#        Lock; indicates an operation that may require multiple transactions to complete.
PERR#        Parity error; used to report data parity errors during PCI transactions excluding a Special Cycle transaction.
SERR#        System error; used to report address parity errors, data parity errors during a Special Cycle, or any other system error that will be catastrophic.


Expansion Features
The PCI slot in the Power Macintosh 5400 computer does not support the optional 64-bit bus extension signals or cache support signals. For more information about the PCI expansion slot, refer to Designing PCI Cards and Drivers for Power Macintosh Computers.



CSII/PCI-Bus Communications Slot Control lines match up 1:1 with the exception of three missing interrupts of the four available on the 5400's PCI slot.


1    /DCD                  2    /DTR
3    /CTS                   4    /RTS
5    RxD                    6    TxD
7    IN_SENSE            8    SCC_ENAB
9    INT_MIC             10    MIC_SENSE
11    MIC_RET           12    EXT_AUD_L
13    Reserved          14    EXT_AUD_RET
15    GND                16    +12V
17    -5V                  18    +12V
19    SYS_WAKEUP    20    Trickle +5
21    GND                22    GND
23    A1                   24    A0
25    A3                   26    A2
27    +3.3V              28    +3.3V
29    A5                   30    A4
31    A7                   32    A6
33    +5V                 34    +5V
35    A8                   36    C/BE(0)~
37    A10                 38    A9
39    GND               40    GND
41    A12                 42    A11
43    A14                 44    A13
45    C/BE(1)~         46    A15
47    GND               48    Gnd
49    SERR~            50    PAR
51    PERR~            52    SBO~
53    LOCK~            54    SDONE
55    +3.3V              56    +3.3V
57    DEVSEL~         58    STOP~
59    IRDY~             60    TRDY~
61    +5V                62    +5V
63    C/BE(2)~         64    FRAME~
65    A17                 66    A16
67    GND                68    GND
69    A19                 70    A18
71    A21                 72    A20
73    A23                 74    A22
75    GND               76    GND
77    C/BE(3)~        78    IDSEL
79    A25                 80    A24
81    A27                 82    A26
83    +3.3V              84    +3.3V
85    A29                 86    A28
87    A31                 88    A30
89    +5V                90    +5V
91    REQ~             92    GNT~
93    +5V                94    +5V
95    INT~              96    Reserved
97    Reserved        98    RST~
99    GND              100    ReservedÔ
101   CLK              102    Reserved
103   GND             104    Reserved
105   Reserved      106    Reserved
107   Reserved      108    Reserved
109   CommGnd    110    RefGnd
111   AudToSlot     112    AudFromSlot


I'd tried to hijack slot specific signals onto a three slot riser card in lieu of its standard jumper card lines and failed. Now I'm wondering about rewiring the CSII connections to convert it to a PCI Slot at whatever ID its single interrupt puts it?


Designing PCI Cards and Drivers for Power Macintosh Computers doesn't even have a PCI pinout listing!



Edited by Trash80toHP_Mini
apparently I can no longer type/spell.
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I hope my analysis of CSII is helpful. Had to replace delimiting tabs with spaces to get a clear presentation. But I've got simple .TXT/.RTF and AppleWorks spreadsheet files worked out if the raw data would be of help, though it looks like you've already got it into spreadsheet format?


I'll start a new thread about PCI conversion antics if I put together information. Can't wait to see what you come up with about hooking Pi Zero directly to the slot, got a progress report to share?

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