ACER AMERICA CORPORATION
HMB-16/20
|
Card Type |
Memory |
|
Chipset/Controller |
N/A |
|
I/O Options |
None |
|
Maximum DRAM |
8MB (4MB on HPB supplemental memory card) |
|
STARTING ADDRESS | |
|
Address |
JP1 |
|
1.25MB (1MB system RAM) |
Pins 1 & 2 closed |
|
4.25MB (4MB system RAM) |
Pins 2 & 3 closed |
|
PARITY CHECK | ||
|
Enabled |
JP2 | |
|
Enabled |
Pins 2 & 3 closed | |
|
Disabled |
Pins 1 & 2 closed | |
|
MEMORY SIZE | |||
|
Size |
SW1/1 |
SW1/2 |
SW1/3 |
|
2MB |
On |
On |
On |
|
4MB |
Off |
On |
On |
|
6MB |
Off |
Off |
On |
|
8MB |
Off |
Off |
Off |
|
MEMORY READ/WRITE TIMING | |||
|
Card Model/System Speed |
SW1/4 |
TP1 | |
|
HMB-16/100-ns |
On |
Pins 4 & 9, 3 & 8 closed | |
|
HMB-20/85-ns |
On |
Pins 4 & 9, 1 & 6 closed | |
|
HMB-16/85-ns |
Off |
Pins 4 & 9, 3 & 9 closed | |
|
HMB-20/100-ns |
On |
Pins 4 & 9, 1 & 6 closed | |
|
Note: SW1/4 in the on position enables the zero wait state. | |||
|
DRAM CONFIGURATION | |||||
|
Size |
Bank 0 |
Bank 1 |
Bank 2 |
Bank 3 |
Parity Bits |
|
2MB |
(16) 514256 |
None |
None |
None |
(8) 511000 |
|
4MB |
(16) 514256 |
(16) 514256 |
None |
None |
(8) 511000 |
|
6MB |
(16) 514256 |
(16) 514256 |
(16) 514256 |
None |
(8) 511000 |
|
8MB |
(16) 514256 |
(16) 514256 |
(16) 514256 |
(16) 514256 |
(8) 511000 |
|
Note:(1) Banks 2 & 3 are located on the HPB daughter card. | |||||
|
(2) The HMB-16 uses 100-ns 514256 RAM chips and 100-ns 511000 parity chips. | |||||
|
(3) The HMB-20 uses 85-ns 514256 RAM chips and 85-ns 511000 parity chips. | |||||
|
MISCELLANEOUS TECHNICAL NOTES |
|
The HMB-16/20 is for use only in Acer interleaved-memory systems. |