DOS Days

The NEAT (New Enhanced AT) Chipset

Developed by Chips & Technologies in 1986, the NEAT chipset combined a number of discreet logic chips and other chips on the motherboards of the era into 3 larger chips. This helped reduce the cost to manufacture these motherboards and made them more reliable. The NEAT chipset was also more officially called CS8221.

The "CS8221 SOLUTION CHIPSet" chips were:

1) 82C206 - Integrated peripheral controller - the main NEAT chip, which incorporated the 82284 clock generator, 82288 bus controller, 8254 Programmable Interval Timer, two 8259 Programmable Interrupt Controllers, two 8237 DMA controllers, and the MC146818 non-volatile RAM/Realtime clock chip.
2) 82C211 - CPU/Bus controller - provides synchronization and control signals for all buses. The 82C211 also provides an independent AT bus clock and allows for dynamic selection, between the processor clock and the user selectable AT bus clock.
3) 82C212 - Page/interleave and EMS memory controller - provides an interleaved memory sub-system design with page mode operation. It supports up to 8 MB of on-board DRAM with combinations of 64Kbit, 256Kbit and 1 Mbit DRAMs.
4) 82C215 - Data/address buffer - provides the buffering and latching between the local CPU address bus and the Peripheral address bus. It also provides bufferring between the local
CPU data bus and the memory data bus.

There were a number of clones of the NEAT chipset produced by others, including Texas Instruments' TACT82206, UMC 82C206L, and OPTi 82C206.

For more technical information on the NEAT-286 chipset, here's the user manual.

A motherboard from an Octek DCS-286 computer. The four large square chips are the NEAT chipset.

Another NEAT chipset motherboard - this one with an 80286-16 CPU

Another NEAT chipset motherboard - this one is a Mylex PC 80286 from 1988

Here's the boot screen of a 80286-based PC with the NEAT chipset:

The following screens show the "Setup" and "Extended Setup" options:


Commercial PCs that I know used the NEAT chipset are:

  • ABC Compact 286 (possibly?)
  • American Digicom Corp DIGIS-NEAT 286
  • Biostar MB-1212C (SIPP version) 286
  • Biostar MB-1216H 286
  • Deico Electronics PC-286i
  • Diamond Flower TOP-286
  • DTK LS2016 NEAT 286
  • DTK PTM-1232C / PTM-1632C 286 (possibly?)
  • DTK PTM-1233C / PTM-1630C 286 (possibly?)
  • DTK PTM-1261C / PTM-1661C 286 (possibly?)
  • Elitegroup 286B (possibly?)
  • Everex Step 286 (possibly?)
  • Everex Tempo 286/12C (EV-2613) and 286/16C (EV-18122) 286 (possibly?)
  • Hyundai Super 286N (possibly?)
  • Ilon USA M-205 (possibly?)
  • Informtech 286/Supra Model B and Model C (possibly?)
  • Informtech Baby 286MB v1.2 286 (possibly?)
  • Informtech IT286SB and QP286AD 286 (possibly?)
  • Jameco JE3010/JE3011 286
  • Leading Edge Model D2/LPS286 (possibly?)
  • Novas 286 NEAT System 286
  • Packard Bell PB1000 286 (possibly?)
  • Packard Bell PB286B 286 (possibly?)
  • Packard Bell PB635 286 (possibly?)
  • Packard Bell PB686 286 (possibly?)
  • Packard Bell PB800/900 (Revs. C and D) 286 (possibly?)
  • Packard Bell PB800 Pack-Mate 286 (possibly?)
  • PC's Limited 28608L/AT122 286 (possibly?)
  • Philips P3345 386SX
  • Qualogy QPC-5138 286 (possibly?)
  • Singa 286-NEAT 286
  • Tandy 3000 and 3000HD 286 (possibly?)
  • Top Microsystems 286 Model-1007-200 and Model-1010-200 v1.25 286 (possibly?)

Some Drivers and Utilities for the NEAT Chipset:

NEAT Chipset Setup Program (from C&T v1.03 and v1.04) for the 82C206, 82C211 and 82C212 chipset
AMD NEAT Chipset Setup Program and EMS Driver
NEAT Quickset Extended CMOS Setup Utility - for 286, 386SX CS8281
NEAT Chipset EMM Driver - provides LIM 4.0-compliant expanded memory
NEAT Chipset EMM v4.12 Driver
NEAT Chipset UMB Driver - Upper Memory Block (UMB) device driver for NEAT chipsets for 286, 386 and 486
NEAT Chipset UMB Driver (DOS 5.x+) - Upper Memory Block (UMB) device driver for NEAT chipsets for DOS 5.0 and newer
CTMAP - A special DOS Memory Manager/Extender written by Burton Systems Software which works directly with C&T memory controllers including the 82C212. It allows programs to be loaded into upper memory, and potentially increases conventional memory beyond the 640 KB limit.

... and for the newer SCAT chipset (this combined the NEAT chips into one, hence the name: "Single Chip AT"):

SCAT Chipset EMM Driver - Expanded memory device driver for the C&T SCAT (DS82C235)


Chips & Technologies also produced a NEAT chipset for 386DX computers and another one called NEATsx for 386SX PCs.