| ??? 11/22/11 04:27 Modified: 11/22/11 04:27 Read: times |
#184849 - Some of us have those ... even the programmables Responding to: ???'s previous message |
Aubrey Kagan said:
Firstly any i8048/8049 is a ROM product and so cannot be user programmed. They can be externally enabled, bypassing the internal memory (see 8035/9 later). Yes, that's quite true. However, they can be used with external memory just as the 805x's can. Further, the ones I have on hand are ceramic-packaged UV erasable types, i.e. 8748 and 8749. I do have an 8040, which is, in this case, a National Semiconductor part, as there were several manufacturers producing 8048-series parts under Intel license, but the 8040 is a romless (probably meaning buggered-up ROM) intended to work with larger internal read-write memory only, and external program store and XRAM. Do you have the means to program the 8748/9? If not perhaps you should be looking at the i8035/9 which were ROMless versions and were intended to use external EPROM- something like a 2716 or 2732. As I recall it needed an octal latch also to store the lower 8 bits of the address. You do sacrifice the 8 pins of the data port as I/O and also require an i8243 I/O expander to recover the 4 port pins associated with the upper address bits (and gain another 12 I/O pins if memory serves). Since I bought several programmers back in the day, I still have that capability. I might even be persuaded to lend one of them to someone who's anxious to use these old parts. I probably have a few 8749s, 8039s and 8243s at home. I will check.
What about the format of the code - will you need an assembler or is it in machine code already? There's a fellow, named Michael McCarrick, who wrote a fairly decent IDE for 8748's. It has an editor that works much like the one in turbo-C, which sort-of clones the original WordStar. It also provides a simulator and an assembler. It does, of course, assume you have a programmer, though the author would probably still be willing to sell you one of his. -Aubrey These are fun to play with if you used 'em in the old days. I once built a flash tester for a friend of mine who had a photoflash and camera repair business. RE |
| Topic | Author | Date |
| Sourcing historic uCs | 01/01/70 00:00 | |
| Vintage MCUs | 01/01/70 00:00 | |
| 8041 | 01/01/70 00:00 | |
| Unfortunately ... | 01/01/70 00:00 | |
| external execution in '41/'42 | 01/01/70 00:00 | |
| I don't doubt what you said ... | 01/01/70 00:00 | |
| Have some old 8748, 8749 and V20 chips | 01/01/70 00:00 | |
| I've got some other old MCU and MPU chips ... | 01/01/70 00:00 | |
| Can you program them | 01/01/70 00:00 | |
| Some of us have those ... even the programmables | 01/01/70 00:00 | |
| If I can find 'em ... | 01/01/70 00:00 | |
seems still live | 01/01/70 00:00 |