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JonB
October 10th, 2017, 08:49 AM
Hello

I just got a Liveport FDM 180 disk unit. Plugs into the Sorcerer's S100 expansion port. Has anyone got any documentation for it? I have the two sheet user guide but I'm seeking something more technical.

Cheers
JonB

James0555
October 10th, 2017, 02:50 PM
Do you have a picture on the control board - the unit I had years ago (not sure who made it) was a exidy card and 2 MPI drives(IIRC) with a boot cartridge after power on you had to issue go e800 or something like that.

Jim

JonB
October 10th, 2017, 09:50 PM
It's not the same unit. The boot ROM is integrated into the drive itself, apparently.


Front of drive. Looks like a Tandon TM100 unit, save for the mechanical lock button and hard sectored disks.

41250


S-100 interface adapter. Has no markings (on component side). I assume the labelled ICs are ROMs of some sort, which get put at BC00h in the Sorcerer's memory map. I would like to find out the purpose of the DIP switch. Possibly to locate the ROM in Sorcerer memory? The value is 00100001 or 10000100 depending on the orientation; that is 21h or 84h. The edge connector to the left hand side connects via a ribbon cable to the Sorcerer's S-100 expansion bus.

41251


There is a fat ribbon cable running across the top of the drive that joins the S-100 adapter to the drive controller board (pictured below). The cable on the left connects to the (presumed) Shugart interface on the drive. The board is marked "Liveport Ltd 1980 Copyright D C Stevens". An edge connector on the left presumably allows additional drives to be connected.

41252

JonB
October 10th, 2017, 11:43 PM
OK, the ROM is identified as Signetics N82S126N PROM (http://pdf1.alldatasheet.com/datasheet-pdf/view/91519/PHILIPS/N82S126N.html). There are two of them on the S-100 board, labelled 3E and 4E respectively. These are 256x4 ROMs, there are two of them, giving 256 bytes for the Sorcerer's disk boot code.

Does not look like my EPROM reader (TOP 853) can handle these...

However - the DIP switch does appear to locate the boot ROM in memory. I tried turning the first switch off and the Sorcerer reports RAMTOP at 5BFF; looking at the memory from 5C00 - 5CFF appears to show the ROM content. Definitely something odd going on in the upper memory decoding on the Sorcerer's mainboard.

With ROM located at DE00h:
41258

Lots of missing data there!

EDIT: Better ignore that! It's DC00, and I can see the ROM there with the ICE. Duhh.. :headslap:


DC00 F2 2F A2 00 F9 3F C9 CD-A2 0F EB 2A A0 0F 2E 00 ./...?.....*....
DC10 E5 0F 1D 00 01 EF E1 0E-12 0F 06 BD EB 3F 3B 1A .............?;.
DC20 70 BF C0 23 10 0F C0 E1-20 AF 00 11 00 0F 19 22 p..#.... ......"
DC30 A2 0F 36 A0 C0 DF 00 00-00 0F 00 2A A2 0F 7E E6 ..6........*....
DC40 80 CF A9 00 7E EF 0F A8-C0 AF 00 23 B6 FF B7 00 ...........#....
DC50 23 7F AF EB 00 0F 00 00-12 7F 23 88 47 1F 77 23 #.........#.G.w#
DC60 88 4F 0D C2 C2 0F 1A B8-C0 2F A2 00 32 2F 23 7E .O......./..2/#.
DC70 20 EF 24 EE 20 CF D4 00-0C 5F CD 49 00 2F 7E 2B .$. ...._.I./.+
DC80 E6 2F EE 20 C0 DF 00 23-78 EF 08 2B C0 0F 01 06 ./. ...#x..+....
DC90 00 3F 61 0E 09 CF 49 01-04 CF FC 00 22 7F E6 08 .?a...I....."...
DCA0 29 CF 19 01 36 6F 0E 0F-C1 4F 01 C3 01 0F 21 5F )...6o...O....!_
DCB0 01 CF 37 01 C0 DF 00 2A-60 0F 22 A4 00 CF 37 01 ..7....*`."...7.
DCC0 C0 DF 00 2A A0 0F 11 0C-00 1F D1 E9 E1 EF 01 86 ...*............
DCD0 00 CF A6 00 E1 CF 37 01-E1 7F 23 B6 E0 CF 7E E6 ......7...#.....
DCE0 20 7F C2 51 01 0F 4F 3E-F1 DF 01 B7 C0 5F 01 0D ..Q..O>....._..
DCF0 C0 5F 01 C9 00 0F 00 00-00 0F 00 00 00 CF A6 00 ._..............


With ROM located at 5C00h:
41259

So I think the boot ROMs look intact, which is good. There appears to be some oddness around the screen display too - some values are flickering and the address changes from 5Cnn to 1Cnn.

Calling the boot code at 5C00 caused the drive light to flicker and the head carriage appears to be making some weak attempt at moving, but the motor doesn't start. I have seen the motor fire up before though. The head carriage and motor may need lubrication, I have not yet opened the drive up for a service.

[Edit 2: I wasn't able to recreate the drive activity, but I have serviced the head carriage..]

JonB
October 11th, 2017, 02:48 AM
Well I take it back. The CPU is in a socket (circled in red).

You can also see all the patch wires for the memory upgrade (circled in yellow). Fortunately I have the instructions for this, so should be able to derive the circuit.

41262

Time to try the ICE, methinks...

James0555
October 11th, 2017, 03:12 AM
For the DIP switch settings could be negative logic so they could DE or EB but my bet would be DE - which could mean your boot address could be DE00.

Jim

JonB
October 11th, 2017, 04:09 AM
Actually, DC00 as far as I can tell. I edited post #4.

Disassembled it looks like this:



DC00 F2 2F A2 JP P,A22F
DC03 00 NOP
DC04 F9 LD SP,HL
DC05 3F CCF
DC06 C9 RET
DC07 CD A2 0F CALL 0FA2
DC0A EB EX DE,HL
DC0B 2A A0 0F LD HL,(0FA0)
DC0E 2E 00 LD L,00
DC10 E5 PUSH HL
DC11 0F RRCA
DC12 1D DEC E
DC13 00 NOP
DC14 01 EF E1 LD BC,E1EF
DC17 0E 12 LD C,12
DC19 0F RRCA
DC1A 06 BD LD B,BD
DC1C EB EX DE,HL
DC1D 3F CCF
DC1E 3B DEC SP
DC1F 1A LD A,(DE)
DC20 70 LD (HL),B
DC21 BF CP A
DC22 C0 RET NZ
DC23 23 INC HL
DC24 10 0F DJNZ DC35
DC26 C0 RET NZ
DC27 E1 POP HL
DC28 20 AF JR NZ,DBD9
DC2A 00 NOP
DC2B 11 00 0F LD DE,0F00
DC2E 19 ADD HL,DE
DC2F 22 A2 0F LD (0FA2),HL
DC32 36 A0 LD (HL),A0
DC34 C0 RET NZ
DC35 DF RST 18
DC36 00 NOP
DC37 00 NOP
DC38 00 NOP
DC39 0F RRCA
DC3A 00 NOP
DC3B 2A A2 0F LD HL,(0FA2)
DC3E 7E LD A,(HL)
DC3F E6 80 AND 80
DC41 CF RST 08
DC42 A9 XOR C
DC43 00 NOP
DC44 7E LD A,(HL)
DC45 EF RST 28
DC46 0F RRCA
DC47 A8 XOR B
DC48 C0 RET NZ
DC49 AF XOR A
DC4A 00 NOP
DC4B 23 INC HL
DC4C B6 OR (HL)
DC4D FF RST 38
DC4E B7 OR A
DC4F 00 NOP
DC50 23 INC HL
DC51 7F LD A,A
DC52 AF XOR A
DC53 EB EX DE,HL
DC54 00 NOP
DC55 0F RRCA
DC56 00 NOP
DC57 00 NOP
DC58 12 LD (DE),A
DC59 7F LD A,A
DC5A 23 INC HL
DC5B 88 ADC A,B
DC5C 47 LD B,A
DC5D 1F RRA
DC5E 77 LD (HL),A
DC5F 23 INC HL
DC60 88 ADC A,B
DC61 4F LD C,A
DC62 0D DEC C
DC63 C2 C2 0F JP NZ,0FC2
DC66 1A LD A,(DE)
DC67 B8 CP B
DC68 C0 RET NZ
DC69 2F CPL
DC6A A2 AND D
DC6B 00 NOP
DC6C 32 2F 23 LD (232F),A
DC6F 7E LD A,(HL)
DC70 20 EF JR NZ,DC61
DC72 24 INC H
DC73 EE 20 XOR 20
DC75 CF RST 08
DC76 D4 00 0C CALL NC,0C00
DC79 5F LD E,A
DC7A CD 49 00 CALL 0049
DC7D 2F CPL
DC7E 7E LD A,(HL)
DC7F 2B DEC HL
DC80 E6 2F AND 2F
DC82 EE 20 XOR 20
DC84 C0 RET NZ
DC85 DF RST 18
DC86 00 NOP
DC87 23 INC HL
DC88 78 LD A,B
DC89 EF RST 28
DC8A 08 EX AF,AF'
DC8B 2B DEC HL
DC8C C0 RET NZ
DC8D 0F RRCA
DC8E 01 06 00 LD BC,0006
DC91 3F CCF
DC92 61 LD H,C
DC93 0E 09 LD C,09
DC95 CF RST 08
DC96 49 LD C,C
DC97 01 04 CF LD BC,CF04
DC9A FC 00 22 CALL M,2200
DC9D 7F LD A,A
DC9E E6 08 AND 08
DCA0 29 ADD HL,HL
DCA1 CF RST 08
DCA2 19 ADD HL,DE
DCA3 01 36 6F LD BC,6F36
DCA6 0E 0F LD C,0F
DCA8 C1 POP BC
DCA9 4F LD C,A
DCAA 01 C3 01 LD BC,01C3
DCAD 0F RRCA
DCAE 21 5F 01 LD HL,015F
DCB1 CF RST 08
DCB2 37 SCF
DCB3 01 C0 DF LD BC,DFC0
DCB6 00 NOP
DCB7 2A 60 0F LD HL,(0F60)
DCBA 22 A4 00 LD (00A4),HL
DCBD CF RST 08
DCBE 37 SCF
DCBF 01 C0 DF LD BC,DFC0
DCC2 00 NOP
DCC3 2A A0 0F LD HL,(0FA0)
DCC6 11 0C 00 LD DE,000C
DCC9 1F RRA
DCCA D1 POP DE
DCCB E9 JP HL
DCCC E1 POP HL
DCCD EF RST 28
DCCE 01 86 00 LD BC,0086
DCD1 CF RST 08
DCD2 A6 AND (HL)
DCD3 00 NOP
DCD4 E1 POP HL
DCD5 CF RST 08
DCD6 37 SCF
DCD7 01 E1 7F LD BC,7FE1
DCDA 23 INC HL
DCDB B6 OR (HL)
DCDC E0 RET PO
DCDD CF RST 08
DCDE 7E LD A,(HL)
DCDF E6 20 AND 20
DCE1 7F LD A,A
DCE2 C2 51 01 JP NZ,0151
DCE5 0F RRCA
DCE6 4F LD C,A
DCE7 3E F1 LD A,F1
DCE9 DF RST 18
DCEA 01 B7 C0 LD BC,C0B7
DCED 5F LD E,A
DCEE 01 0D C0 LD BC,C00D
DCF1 5F LD E,A
DCF2 01 C9 00 LD BC,00C9
DCF5 0F RRCA
DCF6 00 NOP
DCF7 00 NOP
DCF8 00 NOP
DCF9 0F RRCA
DCFA 00 NOP
DCFB 00 NOP
DCFC 00 NOP
DCFD CF RST 08
DCFE A6 AND (HL)
DCFF 00 NOP


..which seems at least partially corrupted to me.

JonB
October 16th, 2017, 12:41 AM
Hello

I just got a Liveport FDM 180 disk unit. Plugs into the Sorcerer's S100 expansion port. Has anyone got any documentation for it? I have the two sheet user guide but I'm seeking something more technical.

Cheers
JonB

Correction... The Sorcerer's expansion port is not strictly S100; it's just that Exidy produced an expansion box that had an S-100 rack inside, and this plugged into the Sorcerer's non S-100 expansion port.