From WikiChip
SBA - General Instrument
< general instrument(Redirected from GI SBA)

GIM SBA
no photo (ic).svg
Developer General Instrument
Manufacturer General Instrument
Type microcontrollers
Production November, 1977
Architecture 1-bit
ISA SBA
Word size 1 bit
0.125 octets
0.25 nibbles
Technology nMOS
Clock 10 kHz-800 kHz
Package DIP40

The GI SBA (Sequential Boolean Analyzer) was a family of 1-bit microcontrollers developed by General Instrument's Microelectronics division. These microcontrollers served as cheap programmable logic controllers, replacing old relay system.

Members[edit]

Part RAM ROM I/O Ports Notes
SBA 120x1 bits 1024x8 bits 31
SBA-1 120x1 bits 31 external storage
SBA-2 120x1 bits 2048x8 bits 31  ?ever released?

Architecture[edit]

The SBA family had a large number (over 30) of I/O ports that could all be individually accessed programatically. Additionally, it had a relatively complex scheme of data storage. In total there were 120 words (1-bit each). This was broken down into 4 pages of 30 addresses each. The program had to choose which page it was working with currently and once that was done, any address selection was done on that page.

New text document.svg This section requires expansion; you can help adding the missing info.

ISA[edit]

Main article: SBA ISA

The SBA family had 8-bit instructions consisting of instructions with immediate and without immediate values. In total there were 24 instructions used for arithmetic, I/O, and page switching.


Text document with shapes.svg This article is still a stub and needs your attention. You can help improve this article by editing this page and adding the missing information.
designerGeneral Instrument +
full page namegeneral instrument/sba +
instance ofmicrocontroller family +
instruction set architectureSBA +
main designerGeneral Instrument +
manufacturerGeneral Instrument +
nameGIM SBA +
packageDIP40 +
technologynMOS +
word size1 bit (0.125 octets, 0.25 nibbles) +