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Cerial-X2

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 I now show three styles of a RS-232 PCB. Each one has TTL decoding and one type of UART. First one has a single 16550 (not shown) Second one has a choice of 16550 or 6551A but not both. Third one eliminates the patch area and includes a MAX232 type IC that would need to be hand-wired in. Hand-wired PCB, below. 2020/09/26 2020/09/29: Both UARTs now functioning on the hand-wired prototype PCB. 2020/10/22: A dual PCB, where both can function. 2020/11/16: Dual 1550's with full address selection. Second One. You choose which UART to install. Both are wired the same for the FTDI-232-5V connector. The double row of jumpers sets the address for each UART. Third One. 2020/09/26 Hand-wired decoding works. Bicycle spokes give support. Decoding TTL IC's are installed, but not in this pix. Top View, murdered Teensy PCB, added to a holey-pcb. Allows either 16550 or 6551A but not both. And not finished as yet, needs the FTDI connector, xtals, etc. Here it is with all parts stuffed (16550 an
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DriveWire4_HD6309E

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DriveWire4 using an HD63C09EP cpu  on a Tandy Color Computer 3. Below is a text file sent to Discord today, modified again of course. Notes on how it got done. PTB/2020/05/26 I started with: Nitros9-6309L2-3.3.0-dw-30M.dsk (I forget which one that was used here). The files that were needed were obtained from BarryN's .dsk (Discord) I listed on paper with a pencil, the modules  that were missing but were inside of  NITROS9/6309L2/MODULES, rbf & scf. I added llide.dr and i0-ide.dd ( my already setup IDE-hdrive)  to have some permanent storage while I collected those  above modules to one location: /i0/DW6309  for ease of finding them while using kwikgen. At first i missed the module 'dwio' but made  sure that it got installed. All modules are loaded at boot and not added with LOAD. I will try and include the "MDIR" list.  First was a "mdir >/rd0/foo" (ramdisk)  Then "list /rd0/foo > /C1"  then finally found
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Cerial-X

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A 16550 serial port. Here begins another project PCB. This one has a UART 16550, a Lattice 2032 CPLD for addressing selection,  and a header for a FTDI-232-5V USB cable. Plus a small patch area Two jumpers for address selection. Several jumpers for wiring connections to the FTDI header. LED for power, LED showing USB has power coming in. LED showing the "FAST" cpu mode. Update: 2020/05/08: It's working at 406800 8N1 baud using a "KTS14,3G2" crystal and xmode bau=6. There was a "challenge" in getting the original crystal to run at each power-up. Addresses: $FF60-FF67 $FF68-FF6F and one custom: $FF28-FF2F. (this one seems broken) With one jumper left, another two selection range could be added. Measurements in mm. As sent in for fab. Here it is plugged into a buffered Y-cable while running NitrOS-9 EOU5. Two of the yellow LED's are lit, one is USB power and the other is PCB power. The third L
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MyDesk Circa 199X

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Pictures from my old backed-up website that now has PORN attached, someone's backup of my old stuff. Don't go there. Here is my coco3 with: NoCan-8MB Custom keyboard     Got tired of trying to fix dying coco3 keyboards...:-) 4-high stack of hard-drives     Just using the top one for now     The next two drives are the normally used ones     Bottom one is for backups 3-high stack of floppy drives     /d0 = 80 tks DS-DD     /d1 = 80 tks DS-DD     /d2 = 80 tks DS-2HD or quad-density Not visible CD-R on shelf above PC-jr. monitor - with sound Modified floppy controller (to do QD floppies)     Without case but has clear plastic cover. Tiny-IDE controller     Follow the IDE cable back     Sitting at an angle w/ frosted cover over the chip (fragile!) PLCC FlashROM - 28F020     Has 2 different CTRL-ALT-RESET pictures, one bart another a logo.     and 6 different CTRL-ALT-RESET boot-nitros9 options PC-power supply     With lots of extra connectors and adapters!
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CoCo Edge Buffer

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Finally, a buffered Y-Cable. Feb/14/2019: Some text corrections. Update: March 16, 2019 2020/06/26: New Cable added. Starts with this PCB: Note that X1 is un-buffered, and X3 is the Y-Cable side. Then that PCB gets slightly modified and includes an overlay PCB with a isplsi2032a CPLD which acts like an MPI PAL. This cable has three IDC 40-pin card edge connectors installed. One for the SDC, one for an IDE controller, and one spare. This particular IDE controller is still in development stage. Plus these PCB's fit the small empty game boxes. That buffered PCB with the hand-wired CPLD (upside-down) and plugs into X1 on the buffer PCB. The cable does need to be "side swapped" as witnessed by the twisted pairs. When the output pins are installed on the bottom of this PCB, then no cable pair swapping is needed, just plug the Y-cable into the bottom located pins. This hand-wired PCB will be a real PC
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Compact IDE Controller PCB

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A compact IDE controller PCB for coco's. Update: 12/11/2018: PCB is here! Dec/20/2018: Identifying a NitrOS-9 device descriptor. Jan/25/2019: TQFP and case Feb/2/2019: More Info Feb/14/2019: Bad news and Good news. Feb/25/2019: Driver Update. A preliminary PCB layout, not in fiberglass yet. Measurements in mm. This PCB could  does support the NitrOS-9 EOU alpha-3 drivers. Items: GCC jumper selects Glenside addressing or inverted addressing. A4, A5, A6 jumpers re-address this PCB into most usable I/O spaces. CS1 jumper for those who want it. (removed) Drive activity LED header.. Power LED. Lattice JTAG-8 header. Yes, it's an "OLD-SCHOOL" CPLD. Showing the ground plane. Actually the labels A0, A1, A2 should be A4, A5, A6. No jumpers needed to match a GCC PCB, for $FF70. Here was the original, now MIA. Sitting on top of a CoCo-3 keyboard. It did control two hard drives. Green activity LED
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8MB setup for a Tandy CoCo3

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Years ago the NoCan series of add-on PCB's was developed. Now today with more resources available to use, the NoCan-8MB is back. The first go-around is a prototype unit only. Updated: Aug/30/2018 Here is a single picture of the current setup. Since the PCB layout limits the size of any PCB, it's in two pieces currently. A memory PCB (left PCB) and a DAT PCB. It started with the 2MB setup and received some hand-added wires to use up the rest of that 16 x 4 SRAM (74LS189). The 8-wire cable at the bottom of the DAT PCB (right PCB) is the JTAG connection. It was tested with Robert Gault's memory test software, originally designed strictly for the NoCan-8MB boards. Thanks Robert! I used the same memory PCB and stuffed another DAT PCB to test an 8MB CPLD. How to use the extra 6MB in a NoCan-8MB device. The following initializes a ramdisk already named "/r0" (/rzero),  and fills it with the contents of /DD/CMDS. <enter> Means
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