Home > Archive > Cobol > June 2004 > IBM 1401 was: Re: Is it possible to use the value of the PROGRAM
You are viewing an archived Text-only version of the thread.
To view this thread in it's original format and/or if you want to reply to
this thread please [click here]
| Author |
IBM 1401 was: Re: Is it possible to use the value of the PROGRAM
|
|
| Clark F. Morris, Jr. 2004-06-12, 8:55 pm |
| Chuck Stevens wrote:
>
> Moreover, there is nothing except resources and incentive preventing an
> obsolete-computer buff from implementing a fully-2002-compliant COBOL
> implementation on a Burroughs B3500, or even an IBM 1401, for which
> architectures the concept of "fixed-length words" as I understand the
> concept does not exist.
I remember the 1401. It had characters with six bits plus a word mark
bit. All fields were terminated by a word mark, a record mark or a
group mark. I forget whether the group mark was a record mark with the
word mark bit set or a record mark was a group mark with the word mark
bit set. The 1401/1440 definitely could not handle the 2002 standard
with only three character addresses maximum and I doubt the big brothers
1410/7010 would have been equal to the task. With all fields being
variable, the series was not well suited to COBOL with multiple record
formats. Many of the instructions were variable length of 1, 4 or 7
characters. The Move Instruction M meant Move A to B stopping at the
word mark. If an address was omitted it meant pick up where the
previous instruction left off. All told an intriguing machine.
Emulation on Intel would be interesting. It probably would be slow.
>
> -Chuck Stevens
>
>
| |
| Kindrick Ownby 2004-06-14, 8:55 pm |
| Chuck Stevens wrote:
[...]
> I maintain that *given enough time* you could do anything on a 1401. It
> might not be easy. It might not be straightforward. But presuming the task
> at hand did not require peripherals unavailable on a 1401 it is *doable* if
> you're willing to wait long enough.
[...]
My 1401 story is more mundane - the company had payroll
running on a 16K 1401 with multiply/divide, and wanted
to downgrade to a 4K 1401 without multiply/divide. They
did retain tape, on which I developed macros for the
multiply/divide, and on which I could store intermediate
results. The resulting program had two phases, with the
data cards inserted between the two portions of the program.
Kindrick
|
|
|
|
|