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V/+HARDW1
This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.
Some of these files were originally commercial releases in the 1980s and 1990s, but they are now widely available online. I assume that copyright over them is no longer being asserted. If you own the copyright and would like files to be removed, please contact me.
| Tape/disk: | Home » Personal collection » Acorn ADFS disks » Electron_User_Group » EUG_56.ADF |
| Filename: | V/+HARDW1 |
| Read OK: | ✔ |
| File size: | 0B54 bytes |
| Load address: | 2B204556 |
| Exec address: | 44524148 |
Duplicates
There are 2 duplicate copies of this file in the archive:
- AEW website » eug » eug_3_5_discs_Eug-56_A-EUG56.adf » V/+HARDW1
- AEW website » eug » eug_5_25_discs_Eug-56_D-EUG56.dsd » V.+HARDW1
- Personal collection » Acorn ADFS disks » Electron_User_Group » EUG_56.ADF » V/+HARDW1
File contents
2M/8M RAM DISK BOARD WITH 24bBC BUS
By Robert Sprowson
THIS hardware project consists of a ready made printed circuit board
(available separately) which, when populated by the following list of
parts forms a 24bBC address decoding board.
Building such a board from scratch on strip board makes quite a large
final board so by using surface-mounted parts, the physical six of the
board can be reduced to 3" by 3.5". Anyone wishing to build one from
scratch can do so by consulting the 24bBC document.
A 24 bit address bus has 16 million unique addresses, half of which
have been set aside for a fast RAM disk with associated RAM filing sys-
tem (available separately). So about a third of this 3" by 3.5" board is
occupied by sockets for RAM chips for this purpose.
Operation of this design is covered in the 24bBC article elsewhere on
this disk.
Parts
THE schematic shows an outline of the following parts and their relative
positions on the board:
3 x 74ALS990 in SOIC package (U5,6,7)
4 x 74HC02 in SOIC package (U11,12,13,9)
1 x 74HC139 in SOIC package (U8)
1 x 74HC00 in SOIC package (U14)
1 x 74HC138 in SOIC package (U3)
1 x 4075BE in SOIC package (U15)
1 x 470uF capacitor, radial leads (C1)
1 x 1.3mm PCB mount power socket (SK4)
8 x 100nF capacitor in 0805 outline (Grey shaded areas)
1 x 34 pin IDC header (SK2)
1 x Fuse holder plus 200mA fuse (FS1)
2 x Turned pin 32 pin DIL chip sockets (SK9,10 - can be omitted)
1 x 34 pin IDC plug
2 feet of 34 way ribbon cable
If there are known to be no other boxes on the 1MHz bus then the card
must be terminated with:
4 x 9 pin SIL array 2.2k resistor packs
If there are other devices daisy chained through the board then you will
need a socket for the next device to plug into:
1 x 34 pin board mount non locking IDC socket (SK1)
If there might be devices daisy chained on the 1MHz bus some of the time
and sometimes not, the terminating resistors should be socketed too:
4 x 9 pin SIL array 2.2k resistor packs
1 x 34 pin board mount non locking IDC socket (SK1)
4 x Turned pin 9 way SIL socket (SK5,6,7,8)
The amount of RAM fitted is entirely optional, and automatically detect-
ed by the RAM filing system software:
1 or 2 x KM681000 (128k x 8bit SRAM) or equivalent in a 32 pin DIL
package
1 or 2 x KM684000 (512k x 8bit SRAM) or equivalent in a 32 pin DIL
package
Optional parts not required by the RAM disk (see below)
1 x 74HC138 (U4)
1 x 7805 voltage regulator in TO220 case (U10)
Benefits
* Tiny design is even smaller than a 3.5" floppy disk
* Very low power, drawing only 125mA
* Special 21 pin expansion header gives the designer the option to add
other peripherals to the 24bBC bus or even more RAM
* Potentially up to 1 Megabyte of storage on board (or 8 Megabytes
using the expansion header)
See the accompanying article (V.+HARDW2) for how to build it.
00000000 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 00000010 20 32 4d 2f 38 4d 20 52 41 4d 20 44 49 53 4b 20 | 2M/8M RAM DISK | 00000020 42 4f 41 52 44 20 57 49 54 48 20 32 34 62 42 43 |BOARD WITH 24bBC| 00000030 20 42 55 53 0d 20 20 20 20 20 20 20 20 20 20 20 | BUS. | 00000040 20 20 20 20 20 20 20 20 20 20 20 20 20 20 42 79 | By| 00000050 20 52 6f 62 65 72 74 20 53 70 72 6f 77 73 6f 6e | Robert Sprowson| 00000060 0d 0d 54 48 49 53 20 68 61 72 64 77 61 72 65 20 |..THIS hardware | 00000070 70 72 6f 6a 65 63 74 20 63 6f 6e 73 69 73 74 73 |project consists| 00000080 20 6f 66 20 61 20 72 65 61 64 79 20 6d 61 64 65 | of a ready made| 00000090 20 70 72 69 6e 74 65 64 20 63 69 72 63 75 69 74 | printed circuit| 000000a0 20 62 6f 61 72 64 0d 28 61 76 61 69 6c 61 62 6c | board.(availabl| 000000b0 65 20 73 65 70 61 72 61 74 65 6c 79 29 20 77 68 |e separately) wh| 000000c0 69 63 68 2c 20 77 68 65 6e 20 70 6f 70 75 6c 61 |ich, when popula| 000000d0 74 65 64 20 62 79 20 74 68 65 20 66 6f 6c 6c 6f |ted by the follo| 000000e0 77 69 6e 67 20 6c 69 73 74 20 6f 66 0d 70 61 72 |wing list of.par| 000000f0 74 73 20 66 6f 72 6d 73 20 61 20 32 34 62 42 43 |ts forms a 24bBC| 00000100 20 61 64 64 72 65 73 73 20 64 65 63 6f 64 69 6e | address decodin| 00000110 67 20 62 6f 61 72 64 2e 0d 20 20 20 42 75 69 6c |g board.. Buil| 00000120 64 69 6e 67 20 73 75 63 68 20 61 20 62 6f 61 72 |ding such a boar| 00000130 64 20 66 72 6f 6d 20 73 63 72 61 74 63 68 20 6f |d from scratch o| 00000140 6e 20 73 74 72 69 70 20 62 6f 61 72 64 20 6d 61 |n strip board ma| 00000150 6b 65 73 20 71 75 69 74 65 20 61 20 6c 61 72 67 |kes quite a larg| 00000160 65 0d 66 69 6e 61 6c 20 62 6f 61 72 64 20 73 6f |e.final board so| 00000170 20 62 79 20 75 73 69 6e 67 20 73 75 72 66 61 63 | by using surfac| 00000180 65 2d 6d 6f 75 6e 74 65 64 20 70 61 72 74 73 2c |e-mounted parts,| 00000190 20 74 68 65 20 70 68 79 73 69 63 61 6c 20 73 69 | the physical si| 000001a0 78 20 6f 66 20 74 68 65 0d 62 6f 61 72 64 20 63 |x of the.board c| 000001b0 61 6e 20 62 65 20 72 65 64 75 63 65 64 20 74 6f |an be reduced to| 000001c0 20 33 22 20 62 79 20 33 2e 35 22 2e 20 41 6e 79 | 3" by 3.5". Any| 000001d0 6f 6e 65 20 77 69 73 68 69 6e 67 20 74 6f 20 62 |one wishing to b| 000001e0 75 69 6c 64 20 6f 6e 65 20 66 72 6f 6d 0d 73 63 |uild one from.sc| 000001f0 72 61 74 63 68 20 63 61 6e 20 64 6f 20 73 6f 20 |ratch can do so | 00000200 62 79 20 63 6f 6e 73 75 6c 74 69 6e 67 20 74 68 |by consulting th| 00000210 65 20 32 34 62 42 43 20 64 6f 63 75 6d 65 6e 74 |e 24bBC document| 00000220 2e 0d 20 20 20 41 20 32 34 20 62 69 74 20 61 64 |.. A 24 bit ad| 00000230 64 72 65 73 73 20 62 75 73 20 68 61 73 20 31 36 |dress bus has 16| 00000240 20 6d 69 6c 6c 69 6f 6e 20 75 6e 69 71 75 65 20 | million unique | 00000250 61 64 64 72 65 73 73 65 73 2c 20 68 61 6c 66 20 |addresses, half | 00000260 6f 66 20 77 68 69 63 68 0d 68 61 76 65 20 62 65 |of which.have be| 00000270 65 6e 20 73 65 74 20 61 73 69 64 65 20 66 6f 72 |en set aside for| 00000280 20 61 20 66 61 73 74 20 52 41 4d 20 64 69 73 6b | a fast RAM disk| 00000290 20 77 69 74 68 20 61 73 73 6f 63 69 61 74 65 64 | with associated| 000002a0 20 52 41 4d 20 66 69 6c 69 6e 67 20 73 79 73 2d | RAM filing sys-| 000002b0 0d 74 65 6d 20 28 61 76 61 69 6c 61 62 6c 65 20 |.tem (available | 000002c0 73 65 70 61 72 61 74 65 6c 79 29 2e 20 53 6f 20 |separately). So | 000002d0 61 62 6f 75 74 20 61 20 74 68 69 72 64 20 6f 66 |about a third of| 000002e0 20 74 68 69 73 20 33 22 20 62 79 20 33 2e 35 22 | this 3" by 3.5"| 000002f0 20 62 6f 61 72 64 20 69 73 0d 6f 63 63 75 70 69 | board is.occupi| 00000300 65 64 20 62 79 20 73 6f 63 6b 65 74 73 20 66 6f |ed by sockets fo| 00000310 72 20 52 41 4d 20 63 68 69 70 73 20 66 6f 72 20 |r RAM chips for | 00000320 74 68 69 73 20 70 75 72 70 6f 73 65 2e 0d 20 20 |this purpose.. | 00000330 20 4f 70 65 72 61 74 69 6f 6e 20 6f 66 20 74 68 | Operation of th| 00000340 69 73 20 64 65 73 69 67 6e 20 69 73 20 63 6f 76 |is design is cov| 00000350 65 72 65 64 20 69 6e 20 74 68 65 20 32 34 62 42 |ered in the 24bB| 00000360 43 20 61 72 74 69 63 6c 65 20 65 6c 73 65 77 68 |C article elsewh| 00000370 65 72 65 20 6f 6e 0d 74 68 69 73 20 64 69 73 6b |ere on.this disk| 00000380 2e 0d 0d 50 61 72 74 73 0d 54 48 45 20 73 63 68 |...Parts.THE sch| 00000390 65 6d 61 74 69 63 20 73 68 6f 77 73 20 61 6e 20 |ematic shows an | 000003a0 6f 75 74 6c 69 6e 65 20 6f 66 20 74 68 65 20 66 |outline of the f| 000003b0 6f 6c 6c 6f 77 69 6e 67 20 70 61 72 74 73 20 61 |ollowing parts a| 000003c0 6e 64 20 74 68 65 69 72 20 72 65 6c 61 74 69 76 |nd their relativ| 000003d0 65 0d 70 6f 73 69 74 69 6f 6e 73 20 6f 6e 20 74 |e.positions on t| 000003e0 68 65 20 62 6f 61 72 64 3a 0d 33 20 78 20 37 34 |he board:.3 x 74| 000003f0 41 4c 53 39 39 30 20 69 6e 20 53 4f 49 43 20 70 |ALS990 in SOIC p| 00000400 61 63 6b 61 67 65 20 28 55 35 2c 36 2c 37 29 0d |ackage (U5,6,7).| 00000410 34 20 78 20 37 34 48 43 30 32 20 69 6e 20 53 4f |4 x 74HC02 in SO| 00000420 49 43 20 70 61 63 6b 61 67 65 20 28 55 31 31 2c |IC package (U11,| 00000430 31 32 2c 31 33 2c 39 29 0d 31 20 78 20 37 34 48 |12,13,9).1 x 74H| 00000440 43 31 33 39 20 69 6e 20 53 4f 49 43 20 70 61 63 |C139 in SOIC pac| 00000450 6b 61 67 65 20 28 55 38 29 0d 31 20 78 20 37 34 |kage (U8).1 x 74| 00000460 48 43 30 30 20 69 6e 20 53 4f 49 43 20 70 61 63 |HC00 in SOIC pac| 00000470 6b 61 67 65 20 28 55 31 34 29 0d 31 20 78 20 37 |kage (U14).1 x 7| 00000480 34 48 43 31 33 38 20 69 6e 20 53 4f 49 43 20 70 |4HC138 in SOIC p| 00000490 61 63 6b 61 67 65 20 28 55 33 29 0d 31 20 78 20 |ackage (U3).1 x | 000004a0 34 30 37 35 42 45 20 69 6e 20 53 4f 49 43 20 70 |4075BE in SOIC p| 000004b0 61 63 6b 61 67 65 20 28 55 31 35 29 0d 31 20 78 |ackage (U15).1 x| 000004c0 20 34 37 30 75 46 20 63 61 70 61 63 69 74 6f 72 | 470uF capacitor| 000004d0 2c 20 72 61 64 69 61 6c 20 6c 65 61 64 73 20 28 |, radial leads (| 000004e0 43 31 29 0d 31 20 78 20 31 2e 33 6d 6d 20 50 43 |C1).1 x 1.3mm PC| 000004f0 42 20 6d 6f 75 6e 74 20 70 6f 77 65 72 20 73 6f |B mount power so| 00000500 63 6b 65 74 20 28 53 4b 34 29 0d 38 20 78 20 31 |cket (SK4).8 x 1| 00000510 30 30 6e 46 20 63 61 70 61 63 69 74 6f 72 20 69 |00nF capacitor i| 00000520 6e 20 30 38 30 35 20 6f 75 74 6c 69 6e 65 20 28 |n 0805 outline (| 00000530 47 72 65 79 20 73 68 61 64 65 64 20 61 72 65 61 |Grey shaded area| 00000540 73 29 0d 31 20 78 20 33 34 20 70 69 6e 20 49 44 |s).1 x 34 pin ID| 00000550 43 20 68 65 61 64 65 72 20 28 53 4b 32 29 0d 31 |C header (SK2).1| 00000560 20 78 20 46 75 73 65 20 68 6f 6c 64 65 72 20 70 | x Fuse holder p| 00000570 6c 75 73 20 32 30 30 6d 41 20 66 75 73 65 20 28 |lus 200mA fuse (| 00000580 46 53 31 29 0d 32 20 78 20 54 75 72 6e 65 64 20 |FS1).2 x Turned | 00000590 70 69 6e 20 33 32 20 70 69 6e 20 44 49 4c 20 63 |pin 32 pin DIL c| 000005a0 68 69 70 20 73 6f 63 6b 65 74 73 20 28 53 4b 39 |hip sockets (SK9| 000005b0 2c 31 30 20 2d 20 63 61 6e 20 62 65 20 6f 6d 69 |,10 - can be omi| 000005c0 74 74 65 64 29 0d 31 20 78 20 33 34 20 70 69 6e |tted).1 x 34 pin| 000005d0 20 49 44 43 20 70 6c 75 67 0d 32 20 66 65 65 74 | IDC plug.2 feet| 000005e0 20 6f 66 20 33 34 20 77 61 79 20 72 69 62 62 6f | of 34 way ribbo| 000005f0 6e 20 63 61 62 6c 65 0d 0d 49 66 20 74 68 65 72 |n cable..If ther| 00000600 65 20 61 72 65 20 6b 6e 6f 77 6e 20 74 6f 20 62 |e are known to b| 00000610 65 20 6e 6f 20 6f 74 68 65 72 20 62 6f 78 65 73 |e no other boxes| 00000620 20 6f 6e 20 74 68 65 20 31 4d 48 7a 20 62 75 73 | on the 1MHz bus| 00000630 20 74 68 65 6e 20 74 68 65 20 63 61 72 64 0d 6d | then the card.m| 00000640 75 73 74 20 62 65 20 74 65 72 6d 69 6e 61 74 65 |ust be terminate| 00000650 64 20 77 69 74 68 3a 0d 34 20 78 20 39 20 70 69 |d with:.4 x 9 pi| 00000660 6e 20 53 49 4c 20 61 72 72 61 79 20 32 2e 32 6b |n SIL array 2.2k| 00000670 20 72 65 73 69 73 74 6f 72 20 70 61 63 6b 73 0d | resistor packs.| 00000680 0d 49 66 20 74 68 65 72 65 20 61 72 65 20 6f 74 |.If there are ot| 00000690 68 65 72 20 64 65 76 69 63 65 73 20 64 61 69 73 |her devices dais| 000006a0 79 20 63 68 61 69 6e 65 64 20 74 68 72 6f 75 67 |y chained throug| 000006b0 68 20 74 68 65 20 62 6f 61 72 64 20 74 68 65 6e |h the board then| 000006c0 20 79 6f 75 20 77 69 6c 6c 0d 6e 65 65 64 20 61 | you will.need a| 000006d0 20 73 6f 63 6b 65 74 20 66 6f 72 20 74 68 65 20 | socket for the | 000006e0 6e 65 78 74 20 64 65 76 69 63 65 20 74 6f 20 70 |next device to p| 000006f0 6c 75 67 20 69 6e 74 6f 3a 0d 31 20 78 20 33 34 |lug into:.1 x 34| 00000700 20 70 69 6e 20 62 6f 61 72 64 20 6d 6f 75 6e 74 | pin board mount| 00000710 20 6e 6f 6e 20 6c 6f 63 6b 69 6e 67 20 49 44 43 | non locking IDC| 00000720 20 73 6f 63 6b 65 74 20 28 53 4b 31 29 0d 0d 49 | socket (SK1)..I| 00000730 66 20 74 68 65 72 65 20 6d 69 67 68 74 20 62 65 |f there might be| 00000740 20 64 65 76 69 63 65 73 20 64 61 69 73 79 20 63 | devices daisy c| 00000750 68 61 69 6e 65 64 20 6f 6e 20 74 68 65 20 31 4d |hained on the 1M| 00000760 48 7a 20 62 75 73 20 73 6f 6d 65 20 6f 66 20 74 |Hz bus some of t| 00000770 68 65 20 74 69 6d 65 0d 61 6e 64 20 73 6f 6d 65 |he time.and some| 00000780 74 69 6d 65 73 20 6e 6f 74 2c 20 74 68 65 20 74 |times not, the t| 00000790 65 72 6d 69 6e 61 74 69 6e 67 20 72 65 73 69 73 |erminating resis| 000007a0 74 6f 72 73 20 73 68 6f 75 6c 64 20 62 65 20 73 |tors should be s| 000007b0 6f 63 6b 65 74 65 64 20 74 6f 6f 3a 0d 34 20 78 |ocketed too:.4 x| 000007c0 20 39 20 70 69 6e 20 53 49 4c 20 61 72 72 61 79 | 9 pin SIL array| 000007d0 20 32 2e 32 6b 20 72 65 73 69 73 74 6f 72 20 70 | 2.2k resistor p| 000007e0 61 63 6b 73 0d 31 20 78 20 33 34 20 70 69 6e 20 |acks.1 x 34 pin | 000007f0 62 6f 61 72 64 20 6d 6f 75 6e 74 20 6e 6f 6e 20 |board mount non | 00000800 6c 6f 63 6b 69 6e 67 20 49 44 43 20 73 6f 63 6b |locking IDC sock| 00000810 65 74 20 28 53 4b 31 29 0d 34 20 78 20 54 75 72 |et (SK1).4 x Tur| 00000820 6e 65 64 20 70 69 6e 20 39 20 77 61 79 20 53 49 |ned pin 9 way SI| 00000830 4c 20 73 6f 63 6b 65 74 20 28 53 4b 35 2c 36 2c |L socket (SK5,6,| 00000840 37 2c 38 29 0d 0d 54 68 65 20 61 6d 6f 75 6e 74 |7,8)..The amount| 00000850 20 6f 66 20 52 41 4d 20 66 69 74 74 65 64 20 69 | of RAM fitted i| 00000860 73 20 65 6e 74 69 72 65 6c 79 20 6f 70 74 69 6f |s entirely optio| 00000870 6e 61 6c 2c 20 61 6e 64 20 61 75 74 6f 6d 61 74 |nal, and automat| 00000880 69 63 61 6c 6c 79 20 64 65 74 65 63 74 2d 0d 65 |ically detect-.e| 00000890 64 20 62 79 20 74 68 65 20 52 41 4d 20 66 69 6c |d by the RAM fil| 000008a0 69 6e 67 20 73 79 73 74 65 6d 20 73 6f 66 74 77 |ing system softw| 000008b0 61 72 65 3a 0d 31 20 6f 72 20 32 20 78 20 4b 4d |are:.1 or 2 x KM| 000008c0 36 38 31 30 30 30 20 28 31 32 38 6b 20 78 20 38 |681000 (128k x 8| 000008d0 62 69 74 20 53 52 41 4d 29 20 6f 72 20 65 71 75 |bit SRAM) or equ| 000008e0 69 76 61 6c 65 6e 74 20 69 6e 20 61 20 33 32 20 |ivalent in a 32 | 000008f0 70 69 6e 20 44 49 4c 20 0d 70 61 63 6b 61 67 65 |pin DIL .package| 00000900 0d 31 20 6f 72 20 32 20 78 20 4b 4d 36 38 34 30 |.1 or 2 x KM6840| 00000910 30 30 20 28 35 31 32 6b 20 78 20 38 62 69 74 20 |00 (512k x 8bit | 00000920 53 52 41 4d 29 20 6f 72 20 65 71 75 69 76 61 6c |SRAM) or equival| 00000930 65 6e 74 20 69 6e 20 61 20 33 32 20 70 69 6e 20 |ent in a 32 pin | 00000940 44 49 4c 20 0d 70 61 63 6b 61 67 65 0d 0d 4f 70 |DIL .package..Op| 00000950 74 69 6f 6e 61 6c 20 70 61 72 74 73 20 6e 6f 74 |tional parts not| 00000960 20 72 65 71 75 69 72 65 64 20 62 79 20 74 68 65 | required by the| 00000970 20 52 41 4d 20 64 69 73 6b 20 28 73 65 65 20 62 | RAM disk (see b| 00000980 65 6c 6f 77 29 0d 31 20 78 20 37 34 48 43 31 33 |elow).1 x 74HC13| 00000990 38 20 28 55 34 29 0d 31 20 78 20 37 38 30 35 20 |8 (U4).1 x 7805 | 000009a0 76 6f 6c 74 61 67 65 20 72 65 67 75 6c 61 74 6f |voltage regulato| 000009b0 72 20 69 6e 20 54 4f 32 32 30 20 63 61 73 65 20 |r in TO220 case | 000009c0 28 55 31 30 29 0d 0d 42 65 6e 65 66 69 74 73 0d |(U10)..Benefits.| 000009d0 2a 20 20 20 54 69 6e 79 20 64 65 73 69 67 6e 20 |* Tiny design | 000009e0 69 73 20 65 76 65 6e 20 73 6d 61 6c 6c 65 72 20 |is even smaller | 000009f0 74 68 61 6e 20 61 20 33 2e 35 22 20 66 6c 6f 70 |than a 3.5" flop| 00000a00 70 79 20 64 69 73 6b 0d 2a 20 20 20 56 65 72 79 |py disk.* Very| 00000a10 20 6c 6f 77 20 70 6f 77 65 72 2c 20 64 72 61 77 | low power, draw| 00000a20 69 6e 67 20 6f 6e 6c 79 20 31 32 35 6d 41 0d 2a |ing only 125mA.*| 00000a30 20 20 20 53 70 65 63 69 61 6c 20 32 31 20 70 69 | Special 21 pi| 00000a40 6e 20 65 78 70 61 6e 73 69 6f 6e 20 68 65 61 64 |n expansion head| 00000a50 65 72 20 67 69 76 65 73 20 74 68 65 20 64 65 73 |er gives the des| 00000a60 69 67 6e 65 72 20 74 68 65 20 6f 70 74 69 6f 6e |igner the option| 00000a70 20 74 6f 20 61 64 64 0d 20 20 20 20 6f 74 68 65 | to add. othe| 00000a80 72 20 70 65 72 69 70 68 65 72 61 6c 73 20 74 6f |r peripherals to| 00000a90 20 74 68 65 20 32 34 62 42 43 20 62 75 73 20 6f | the 24bBC bus o| 00000aa0 72 20 65 76 65 6e 20 6d 6f 72 65 20 52 41 4d 0d |r even more RAM.| 00000ab0 2a 20 20 20 50 6f 74 65 6e 74 69 61 6c 6c 79 20 |* Potentially | 00000ac0 75 70 20 74 6f 20 31 20 4d 65 67 61 62 79 74 65 |up to 1 Megabyte| 00000ad0 20 6f 66 20 73 74 6f 72 61 67 65 20 6f 6e 20 62 | of storage on b| 00000ae0 6f 61 72 64 20 28 6f 72 20 38 20 4d 65 67 61 62 |oard (or 8 Megab| 00000af0 79 74 65 73 0d 20 20 20 20 75 73 69 6e 67 20 74 |ytes. using t| 00000b00 68 65 20 65 78 70 61 6e 73 69 6f 6e 20 68 65 61 |he expansion hea| 00000b10 64 65 72 29 0d 0d 53 65 65 20 74 68 65 20 61 63 |der)..See the ac| 00000b20 63 6f 6d 70 61 6e 79 69 6e 67 20 61 72 74 69 63 |companying artic| 00000b30 6c 65 20 28 56 2e 2b 48 41 52 44 57 32 29 20 66 |le (V.+HARDW2) f| 00000b40 6f 72 20 68 6f 77 20 74 6f 20 62 75 69 6c 64 20 |or how to build | 00000b50 69 74 2e 0d |it..| 00000b54
V/+HARDW1.m0
V/+HARDW1.m1
V/+HARDW1.m2
V/+HARDW1.m4
V/+HARDW1.m5
.