MARANTZ@RUTGERS.ARPA (08/29/84)
From: Roy <MARANTZ@RUTGERS.ARPA> Anyone have any suggestions for real cheap ($10 - $20) microcomputers. I have a bunch of small projects that I'd like to do and would like to use the same kind of hardware to do them on. I'd ideally like: single chip microcomputer single single power supply voltage CMOS (low power usage in standby at least) small size easy to do clock (builtin or easy to find crystal) I don't really care about the instruction set (too much) or the amount of RAM (I'll use 64 - 256 bytes) or EPROM (1 or 2 K), but it would be nice to have a UART built in. I've been looking around some, but it seems that the price range I'm looking for doesn't have alot to offer (for small quantity). I don't care if it's 4 bit wide (or 32 for that matter), in fact I'm looking into getting a "device controller" since I don't really need most of the micro. Anyway, any suggestions, help, ... would be appreciated. Roy -------
mlsmith@NADC.ARPA@sri-unix.UUCP (08/30/84)
Suggest you look at Intel 80C31, Molorola 146805, and Hitachi (don't know #)
irwin@uiucdcs.UUCP (09/05/84)
It sounds like you should look at the RCA 1802. The plastic version can be purchased for about $2.95. It is cmos, handles up to 64k mem, can be used as a uart via software control, has internal clock osc, (you provide the xtal), has I/O port control and also has built in DMA, (uses R0 to address mem in DMA mode). I have a home micro built around one that I have been using for years, do word processing and other things with it. It is an 8 bit machine, has 16 scratch pad registers which you can assign to stack, pc, or what ever you wish. I have found it to be a handy-dandy little CPU (I got into it because I wanted to put a cmos micro in a model airplane radio control system and needed cmos to get low battery drain).
gnu@sun.uucp (John Gilmore) (09/12/84)
Every keyboard built in the last 3 years uses an 8048 or 8049 single chip micro, or its EPROM version the 8748/8749. They must cost like $1 or less and they're pretty reasonable little beasts if you don't have much of a job to do, e.g. like polling a bunch of switches and sending the transitions down a serial line bit-by-bit, pretending to be a UART.