AnyCPU http://anycpu.org/forum/ |
|
Simple Large Computers http://anycpu.org/forum/viewtopic.php?f=23&t=1009 |
Page 1 of 4 |
Author: | oldben [ Sun May 28, 2023 2:58 am ] | ||
Post subject: | Simple Large Computers | ||
I am expanding a 20 bit design to 36 bits. You have unsigned characters (9) bits or word data (36) bits. The rough draft for the 20 bit cpu is 16 opcodes, as 128 x 16 rom.
|
Author: | oldben [ Sun May 28, 2023 9:13 pm ] |
Post subject: | Re: Simple Large Computers |
The rom's fit into 22v10's. Modified the microcode to use 16v8's for Alu I/O, rather than 22v10's. MMu logic is still up in the air, but the 36 bit CPU looks to fit all on single mid sized PCB. 12" x 10"? Ben. |
Author: | robfinch [ Mon May 29, 2023 3:52 am ] |
Post subject: | Re: Simple Large Computers |
Is this using late 70's technology? Putting any expansion connectors on the board? |
Author: | oldben [ Mon May 29, 2023 8:43 am ] |
Post subject: | Re: Simple Large Computers |
More like the early 1980's. I am trying to squeze 3 1970's PCB's into 1 large PCB. I have rethink the data path again, to get it to flow 8 bits per chip. The pal logic was designed 4 bits per chip using 4 bit wide bit slices. Does any one make 9 bit bit wide memory in thru the hole packaging? |
Author: | robfinch [ Tue May 30, 2023 7:40 am ] |
Post subject: | Re: Simple Large Computers |
Quote: Does any one make 9 bit bit wide memory in thru the hole packaging? There might be a cache tag RAM that is 9 or 10 bits wide. But that is probably not early 80's tech. |
Author: | oldben [ Tue May 30, 2023 7:53 am ] |
Post subject: | Re: Simple Large Computers |
Take 5 min break, and I lose my draft. The design will be similar to a IBM AT ( 6.6 Mhz) and 256kb of ram. The computer will use 2 56 pin connectors per circut board, under each 16 bit alu. A 4 bit 2901 will be in the middle. 8" x 11" pcb seems about right for now. Two data sizes, byte (9 bits unsigned) and word 36 bits. 22v10's will emulate 74F823's and 74827's. (9 bit d f/f and 10 bit buffers). Ben. |
Author: | oldben [ Thu Jun 01, 2023 5:37 am ] |
Post subject: | Re: Simple Large Computers |
This design is July xx 1984. Other than using CMOS chips, it seems buildable (4 layer board may be needed for the large power draw) in that time frame. 22v10 's are must since bytes are 9 bits wide. 20 bits is segment size or 256K words of prgram space. This first version will just have space for the MMU, but no logic to enable it. Modern chips will replace the 64K x 1 drams used. Ben. |
Author: | oldben [ Sat Jun 03, 2023 6:54 pm ] |
Post subject: | Re: Simple Large Computers |
Code: 1981 computer with 9 bits per byte - 36 bit bus 6.66 mhz makes use of 9 bit wide buffers and flip flops. 16 page mmu 512kb segments/ 64k drams 36 bit version 2 meg memory (MAX) 256kb memory 9 8 7 6 5 4 3 2 1 +----+----+----+----+----+----+----+----+----+ |COOO:mAAA:aXXX:SS+#:####:####:####:####:####| +----+----+----+----+----+----+----+----+----+ A X OP CC 0 # Z ST/SN - 1 S S XOR Z 2 X X OR S 3 Y Y AND Z+S 4 A A LD/LN !C 5 B B CAD/CAC !(C+Z) 6 C C SUB/SBC T 7 D D ADD/ADC T SN,LN NO MAP SS 00 word 01 byte signed 10 half unigned 11 half signed Post note, Memory is still to complex with all this byte shifting. 1 st version no mmu 0x0(6/7)0000 maps to 0x1(E/F)0000 ss 00 word ss 01 byte unsigned ss 1x reserved |
Author: | oldben [ Thu Jun 08, 2023 7:26 pm ] |
Post subject: | Re: Simple Large Computers |
Really cutting back on the design hardware wise. Gone to a core style memory cycle. Using 1988 tech to give me a 1968 design. Front panel now just POWER,run and stop. PDP 8/e speed .6 us clock cycle, 1.2 us memory cycle. Just word addressing,18 bits mar, 36 bit bus. Ben. |
Author: | oldben [ Fri Jun 09, 2023 4:35 am ] | ||
Post subject: | Re: Simple Large Computers - switches wanted | ||
Looking for cheap front panel swiches that I can mount on a pcb. I need 36+ switches, and footprints. Any recomendations. Micro slide switches are too small. I am also looking for a LED indicator that has the led, dropping resistor and driver all in the same package.
|
Author: | oldben [ Sat Jun 10, 2023 4:18 am ] |
Post subject: | Re: Simple Large Computers - cmos |
Code: * JUNE 9 2023 draft 36 bit CPU Ben 67 / 1988 version No bytes 4.77 MHZ 1.25 US CORE timing LIMITED front panel 9 8 7 6 5 1 3 2 1 +----+----+----+----+----+----+----+----+----+ |COOO:AAAA:XXXX:MAY+:####:####:####:####:####| +----+----+----+----+----+----+----+----+----+ A OP CC 0 Z A ST - 1 S B XOR Z 2 T C OR S 3 U D AND Z+S 1 V E LD !C 5 W F CAD/CAC !(C+Z) 6 X G SUB/SBC T 7 Y H ADD/ADC T '/' LRDE COMMENT '*' BLOCK COMMENT BEGIN/END ONLY #OOO OCTAL PROGRAM COUNTER TOKENS PROM A PRB# tst 0001 0 ctl 0001 0 y 0002 1 wrd 000C sx 0004 2 +- 20 bits 1 0008 3 op 2000 5' ld 0020 5 sub 2020 no 0040 6 sft 0080 7 PROM B PRB# by 0100 0' not used IR 0800 3' rd 0010 1 wr 0210 1' pc 0000 ac 0040 3 ix 2000 5' RD 1000 1' sp 8000 7' ax 2040 REAL SIMPLE CPU (J-PAN_,ST_)(JMP_,M,A)(cnt) 0 ST_ JMP_,M A NORMAL 1 X PAN_ X X TRAP 1 X PAN_ X X PANEL * #000 / CTL PC Y 1 RD IX CTL NO IR PC RD PC 1 IR #010 / JSV # / SP 1 SUB WR RD PC 1 SUB WR PC LD SX RD PC 1 IR #020 / JMP X IX NO SX RD PC IN PC LD WRD RD PC 1 IR #030 / JMP A+- IX Y SX RD PC IN PC LD WRD RD PC 1 IR #040 / LEA MA 00 PC Y 1 RD AX SX IR PC RD PC 1 IR #050 / LEA MA 01 PC Y 1 RD AX SX IR PC RD PC 1 IR #060 / ST X AX NO SX WR RD AC WR PC RD PC 1 IR #070 / ST A+- IX Y SX WR RD AC WR PC RD PC 1 IR #100 / BCC # IX TST PC RD PC 1 IR PC / TRUE PC LD SX RD PC 1 IR #110 / SCC IX TST PC 1 Y RD IX LD 0 IR PC / TRUE PC 1 Y RD IX LD SX IR #120 / SHIFT X 6 IX SFT IX SFT IX SFT IX SFT IX SFT PC 1 Y RD IX SFT IR #130 / SHIFT PC 1 Y RD IX SFT IR #140 / MEM % PC 1 Y RD AX OP IR #150 / MEM # PC 1 Y RD AC OP SX IR #160 / MEM X AX NO SX RD PC IN PC 1 Y RD AC OP WRD IR #170 / MEM A+ IX SX Y RD PC IN PC 1 Y RD AC OP WRD IR / TRAP DON'T CARE IR RDPUT / PUSH (PC-1), P=1 #240 / TRAP SP 1 SUB WR RD PC 1 SUB WR PC LD 1 RD PC 1 IR #340 / TRAP SP 1 SUB WR RD PC 1 SUB WR PC LD 1 RD PC 1 IR #250 / TRAP SP 1 SUB WR RD PC 1 SUB WR PC LD 1 RD PC 1 IR #350 / TRAP SP 1 SUB WR RD PC 1 SUB WR PC LD 1 RD PC 1 IR #260 / TRAP SP 1 SUB WR RD PC 1 SUB WR PC LD 1 RD PC 1 IR #360 / TRAP SP 1 SUB WR RD PC 1 SUB WR PC LD 1 RD PC 1 IR #270 / TRAP SP 1 SUB WR RD PC 1 SUB WR PC LD 1 RD PC 1 IR #370 / TRAP SP 1 SUB WR RD PC 1 SUB WR PC LD 1 RD PC 1 IR // PANEL #200 / IDLE PC PC PC PC IR #300 / IDLE PC PC PC PC IR // PANEL #210 / ALD PC NO LD OP RD PC IN PC LD WRD PC IR #310 / ALD PC NO LD OP RD PC IN PC LD WRD PC IR #220 / EXAM PC 1 Y RD PC IN PC PC IR #330 / EXAM PC 1 Y RD PC IN PC PC IR #230 / DEP PC NO LD OP RD PC IN PC 1 Y WR RD PC LD NO WRD WR IR #330 / DEP PC NO LD OP RD PC IN PC 1 Y WR RD PC LD NO WRD WR IR * FILES and chips "JTRAP" irq and counter 1 "JALU" alu decode 2 "JCON" control logic 3 "JMEM" memory logic 4 "JMLX" a,b reg logic 5 "JMX?" 1,2,3 input mulx 9 wide 6 7 8 "JROMA" pal - prom a 9 "JROMB" pal - prom b 10 74act14 x 1 inverter 11 74act00 x 1 nand 12 74act823 x 2 ir reg 13 14 74act823 x 4 in reg 15 16 17 18 74act823 x 4 out reg 19 20 21 22 2901C x 1 4 bit slice 23 7C9101 x 2 16 bit slice 24 25 * // ALL DONE A Cmos computer, with 25 chips for the main board ( alu and control logic ). Power down from 8 amps to 1 amp. Simple front panel, but no blinky lights. Having 9 bit wide registers and buffers is so nice. Ben. |
Author: | BigEd [ Sat Jun 10, 2023 6:45 am ] |
Post subject: | Re: Simple Large Computers |
Nice - do you plan to build it? |
Author: | oldben [ Sat Jun 10, 2023 8:10 am ] |
Post subject: | Re: Simple Large Computers |
BigEd wrote: Nice - do you plan to build it? I do plan to build it, at some point. At the moment am gathering collecting parts, mostly from ebay. It is the mechanical parts like switches and leds and connectors that need to played with now for the mother board and front panel layout. I am also in need of a good schematic capture and PCB lay out program that is Imperal not metric in layouts and footprints. I guess I got about 1500 pins per pcb at 8" x 11". I have budget of about $500 Canadian for that. Mechanical construction is my weak point, as all I have the kitchen table and a good soldering iron, and a old drill. Ben. |
Author: | robfinch [ Sun Jun 11, 2023 11:29 am ] |
Post subject: | Re: Simple Large Computers |
Quote: I am also in need of a good schematic capture and PCB lay out program that is Imperal not metric in layouts and footprints. I guess I got about |
Author: | oldben [ Sun Jun 11, 2023 4:13 pm ] |
Post subject: | Re: Simple Large Computers |
Kicad seems still have a footprint problem, and is meteric based. What it I want to use .156 inch spacing connectors, and card edge connectors, or Yang Foo switchs. If sombody came up with a standard library for items like that it would consider it a valid option. Often I want to design a schematic segment, and leave detals like footprints for later. What if part XYX needs a footprint changed later on the PCB lay out. A 7475 vs 74275. I want to start drawing schematics, not makeing components for incomplete libraries, since version #1. This includes old TTL, and other logic, not some new transistor with 5000 lay out patterns, Can kicad import net lists? Can I have design template, so I can start a PCB with the BASIC power and ground and finger routing all done, like a S100 card with fingers and voltage regulators. I want good manual routing, not flaky auto routing. Ben. PS: I also want a game pad as input device for schematic layout. (RS) X to kill that logic bug. To me it makes sense, as game pad has ample buttons for layout, not ALT SHIFT RIGHT FUNCTION 742 to end a line. PPS: I dislike Kicad, for the simple reason they keep revising to a new version every other year, and libraries keep changing. I sill have a few .156 card edge connectors, Yang FOO switches and plan to use fingers on the PCB. |
Page 1 of 4 | All times are UTC |
Powered by phpBB® Forum Software © phpBB Group http://www.phpbb.com/ |