Host Transfer (Sequential) DLP

The Host Transfer (Sequential) DLP is used to connect a medium or v-series system to the B9387 and B9389 disk pack drive controllers. The Sequential version of the Host Transfer DLP supports a sequential layout of sectors on a track providing increased throughput (albeit with less capacity).

B9494-24

The B9494-24 Disk Subsystem (AKA 682) offers a “mega storage” capacity of 5.04GB per unit. A small “string” of B9494-24s provides 20.16 GB of storage.

DPDC I/O Descriptors

Operation MLI OP SYS OP S L1 L2 L3 Addresses
TEST 2 64
Unit * 0 U V
Wait for Ready * 1 U V
Wait for Not Ready * 2 U V
+ Verify (EPC Only) * 4 U V C Address Required
Power Unit Up/Down * 5 U V
Controller Lock
Enable/Disable
* 6 0 V
Maint Mode
Enable/Disable
* 7 U V
Discontinue * A U 0
ID * C 0 0
+ Initialize * D U V C Address Required
Relocate * E U V C Address Required
WRITE 4 62
Data/Conditional * 0 U V A and B Addresses
Data/Unconditional * 1 U V Required
+ Format * 4 U V
Initialize Controller
Parameters
* 8 0 0
Cable Echo * D 0 0
Host Load * E 0 0
Buffer * F U 0
READ 8 60
Data/Conditional * 0 U V A, B and C
Data/Unconditional * 1 U V Required
Transfer * 2 U V
Format * 4 U V
Start Snap * 6 U 0 A and B Required, C MBZ
Extended Status * D 0 0 A and B Required, C MBZ
Unit Status * E U V A and B Required, C MBZ
Buffer * F U 0 A and B Required, C MBZ

U designates unit number.

V in column L3 indicates variant digit. 0 indicates I/O descriptor sent to drive in normal operating mode. 1 Indicates I/O descriptor sent to drive in Maintenance Mode. Variants of other values are described in the DLP Technical Manual.

+ indicates C address must be sector 0 of the cylinder.

Command Formats

4X series system opcodes have two addresses. The A and B addresses are the start and end of the memory transfer buffer. Some operations do not transfer any data other than the command and result descriptors. The A and B addresses are typically set to 0 in this case.

5X series system opcodes have three addresses. The A and B addresses are the start and end of the memory transfer buffer. The C address contains 8 digits of extra parameters for the command. In this case all 8 digits of the C address field are the disk address, which may be in binary or decimal, as required by the drive.

Read Unit Status

The first and second bytes of the buffer returned by the READ UNIT STATUS operation contains the Controller Firmware Version. The fourth byte contains the Drive Type.

Host Transfer (Sequential) DLP Result Descriptor Word 1

A B C D
8 NOT
READY
ZERO INCORRECT
STATE
ZERO
4 UNABLE TO
INITIATE
READ
EXTENDED
STATUS
(BMDUMP)
DISCONTINUED BLTA
VERTICAL
PARITY
ERROR
2 VERTICAL
PARITY ERROR
(MLI)
UNABLE TO
COMPLETE
TIMEOUT BLTA LON-
GITUDINAL
PARITY
ERROR
1 LONGITUDINAL
PARITY
ERROR
(MLI)
INVALID
DESCRIPTOR
ZERO EXCEPTION

Host Transfer (Sequential) DLP Result Descriptor Word 2

A B C D
8 ZERO ZERO SUCCESSFUL
RETRY
CON-
TROLLER
LOCKED
4 ZERO ZERO WRITE
LOCKOUT
ZERO
2 ZERO ZERO ZERO POWER
UP
SUPPORTED
1 CABLE
ERROR
ZERO FIRST
ACTION
ROM
COMMAND
ERROR

Host Transfer (Sequential) DLP Result Descriptor Words 3 and 4

R/D Bits
Word 3 Word 4
A B C D A B C D
Description 8421 8421 8421 8421 8421 8421 8421 8421
Data Error 1111 0000 Sector Address
Seek Error 1111 0001 Sector Address
Address Error 1111 0010 Sector Address
Write Retry 1111 0011 Sector Address
Read Retry 1111 0100 Sector Address
Data Error Correct. 1111 1000 Sector Address
Command Error (B) 1111 1000 Sector Address
Command Error (A) 0000 R/D Tag Command
Disk Error 0001 R/D Tag Disk DDP Status
Disk Error 0100 R/D Tag Disk Unit Status
Disk Error 0101 R/D Tag Drive Msg Word 1
Host Error 0110 R/D Tag Host DDP Status
Processor Error 1001 R/D Tag Memory Status
Controller Failure 1010 R/D Tag Not Used
Exchange 0 Failed 1011 R/D Tag 0000 0000 0000 0000
Exchange 1 Failed 1011 R/D Tag 0001 0000 0000 0000

Host Transfer (Sequential) TEST/ID Result Descriptor Word 2

A B C D
8 0 0 X X
4 0 0 X X
2 1 0 X X
1 1 1 X X

X - field installed jumpers (not used for medium systems)

Each Sequential Host Transfer DLP can be jumpered with a specific code. This code is not used by the V Series MCP and is typically left unjumpered, returning a value of 00. (This feature was implemeted for the Large Systems MCP.)

MCP Considerations

Simulator Commands

The following simulator commands can be used to manipulate the Host Transfer Sequential DLP.

Command Description
channel CC htseq Add a host-transfer sequential DLP at channel CC.
control CC/UU create filename type [LAK] Create a disk or pack unit of the desired type. Type may be one of these. LAK specifies that the device should have 100 byte sectors. If the file already exists, it will be assumed to already contain valid data. If the file doesn't exist, it will be created and truncated to the appropriate size
control CC/UU loadfw vsersion Can be used to pre-load a particular firmware version (e.g. AD) code into the simulated disk/pack controller.
control CC/UU status Displays device status for the selected device.
control CC status Displays device status for all devices on the channel.
vsim> channel 16 htseq
vsim> control 16 loadfw AD
vsim> control 16/0 create diskpacks/206pack1.img 206S
vsim> control 16/1 create diskpacks/682pack2.img 682S
vsim> control 16/2 create diskpacks/shared-207LAK-2.img 207S LAK
vsim> control 16 status
CCCC/UU BPS TYPE TESTS  READS  WRITES  FILE
0016/00 180 206S 000000 000000 000000  diskpacks/206pack1.img
0016/01 180 682S 000000 000000 000000  diskpacks/682pack2.img
0016/02 100 207S 000000 000000 000000  diskpacks/207LAK0.img
0016/03 100 207S 000000 000000 000000  diskpacks/207LAK1.img
vsim> control 16/1 status
CCCC/UU BPS TYPE TESTS  READS  WRITES  FILE
0016/01 180 682S 000000 000000 000000  diskpacks/682pack2.img
dlps/host_transfer_sequential.txt · Last modified: 2009/05/14 07:19 by scott
 
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