I assume the Datapoint 3300 terminal's  electronics beam characters to the
crt differently.  If they're the same, or close enough from the font
perspective, I have a 3300 that works that could be used.  Same goes for
power supply, I have a spare of one of the 3300"s power supplies should it
be used to modified to be used in a 2200.  I.assume it's a long shot..  I
did not look it up to see for sure.

Anyone have a 3300 that needs a power supply?  The 3300 has multiple power
supplies, I have a working spare of the supply that attaches to the back
behind the.crt.

Bill

On Sun, Nov 13, 2022, 4:45 AM jos via cctalk <[email protected]> wrote:

> On 13.11.22 07:13, Steve Lewis via cctalk wrote:
> > I've been looking for a video or image that shows what font the original
> > Datapoint 2200 used.
> >
> > It's not shown in the manual.   There is one vintage image with the
> office
> > lady and the DP2200 on the desk- but the font isn't very clear in that.
> >
> > In any modern video about the DP2200, none of them seem to power it on --
> > which is certainly understandable.   From what I've read, the power
> supply
> > of that system is prone to failure.  Also, the system is hard-coded to
> load
> > from Tape 1 -- which means both the tape drive, and tape media, still
> needs
> > to be in good working order (which would be pretty rare after this time).
> >
> > In "the" DP2200 book, it only briefly mentions that the original tape
> > software was developed "on an HP system" (without any elaboration that I
> > could tell on which HP system that was).
> >
> > Nothing in the manual suggests the original DP2200 could "program itself"
> > (i.e. no built in machine code monitor -- those TTL chips had one strict
> > boot up sequence: load from tape 1).   If there was a read error or no
> tape
> > available, I'm curious if any message showed on the CRT.
> >
> > So, I was just wondering if there was any known pre-1973 Datapoint 2200's
> > that are still working? (and/or if any HD video of them powered on and
> > legible font can be seen)  Or any other more current system that we know
> > for sure used the same font?
> >
> > Thanks!
> > -Steve
>
>
> Not only  is the powersupply prone to failure, it is also the most
> dangerous I have ever seen, and I am hesitant on working it. Primary and
> secondary sides not separated,  isolation between the two almost
> nonexistant, many primary nodes exposed. Would never pass modern safety
> checks.
>
> But here is a picture of my DP1100, a DP2200 derivative, while it was
> running a memory selftest, for a short time in 2021, before the powersupply
> blew again :
>
>
> https://forum.vcfed.org/index.php?threads/its-alive-my-datapoint-2200-1100.1222197/#post-1222197
>
> While the DP2200 is hardcoded to start from tape, the DP1100, otherwise
> identical, boots from a ROM. This ROM also contains a minimal machinecode
> monitor. I recovered & disasembled the ROM and Gordon Peterson, from
> Datapoint, commented it out :
> http://www.bitsavers.org/pdf/datapoint/1100/DisketteBootDisassemblyGEP2.txt
>
> Note that there are multiple videoboard options : the later DP2200, my
> DP1100, and the DP5500 share the same videoboard. This relies on a
> programmable characterset. In the disassembly mentioned above above,
> starting at line 3660 you will see a load of gobldecook, these are actually
> fondsets to be loaded into the machine.
>
> The fontset has a very particular "look" to it. How much is due to
> fontdefinition, and how much is due to the diddlescan, that I dont know.
> Diddlescan is where they scan each character in full, before proceding to
> the next.
>
> Note that a  ROM based bootboard for a DP2200 would be a trivial
> undertaking,  and only involve changing the cassette reader board for the
> ROM board.
>
>
> Jos
>
>
>

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