IBM 3745 Series, Справочник по техническому обслуживанию оборудования

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CA Addressing
PIO Mode
The number of CAs to address is four.
The IOH OUT '07' is the only one which selects a CA. The definition of the
IOH/MIOH bit pattern is:
Ÿ Byte 0, bit 0 of TA time is the IOC connection:
0 = IOC1
Ÿ Byte 0, bits 1-4 is the type address: Code = 0 0 0 1 for all CAs
Ÿ Byte 0, bits 5-7 and byte 1, bits 0-7 is the
command code = 0 0 0 0 1 1 1 x 0 x x
Ÿ Byte 1, bit 4 indicates the origin :
0 = Control program (IOH)
1 = MOSS (MIOH)
Ÿ The remaining part of the address is contained in the TD field. Only the MIOH
command '07' is able to select a channel adapter with the following convention:
– Byte 0, bit 2 is equal to 1 to select a CA indicated by byte 0, bits 4 to 6.
– Byte 0, bits 4 and 5 is the group address:
0 0 = CA Group 1
0 1 = CA Group 2
– Byte 0, bit 6 is the slot address:
0 = Slot 1
1 = Slot 2
Note: In case of TPS, the B interface uses the slots of the following CA, part of
the same CA group. The address of the CA replaced by the B interface is lost.
IOC bus at TA time IOC bus at TD time
Byte ð Byte 1 Byte ð Byte 1
%─────────────5 %─────────────5 %─────────────5 %─────────────5
┌─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┐ ┌─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┐
│ð│1│2│3│4│5│6│7│ð│1│2│3│4│5│6│7│ │ð│1│2│3│4│5│6│7│ð│1│2│3│4│5│6│7│
├─┼─┼─┼─┼─┼─┼─┼─┼─┼─┼─┼─┼─┼─┼─┼─┤ ├─┼─┼─┼─┼─┼─┼─┼─┼─┼─┼─┼─┼─┼─┼─┼─┤
│U│ð│ð│ð│1│X│X│X│X│X│X│X│X│ð│X│X│ │X│X│1│ð│G│G│S│X│X│X│X│X│X│X│X│X│
└─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┘ └─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┘
┬ ───┬─── ─────────┬─────────── ┬ ─┬─ ┬
│ └─── Type └─────── Command │ │ └─── Slot
│ address │ └─── Group address
└─── IOC └─── Select CA
┌─────────┬─────────┐
│ GG = ðð │ GG = ð1 │
│S=ð │S=1 │S=ð │S=1 │
┌───────┼────┼────┼────┼────┤
│ IOC1
│ CA │ CA │ CA │ CA │
│ U = ð │ ð5 │ ð6 │ ð7 │ ð8 │
└───────┴────┴────┴────┴────┘
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IBM 3745 Models 130, 150, 160, 170, and 17A: Hardware Maintenance Reference