I've got this 486 board with this chip on it, that has an oscillator heading to it via another chip. AFAIK it is a RTC, but I can't find a datasheet for it anywhere. Pin 24 isn't connected to 5V, and pins 1 and 4 are tied together on the PCB. on the Motorola part that would be NC and AD0, which doesn't make a lot of sense.
I'm not getting a CLK signal on the ISA bus. So I'm trying to follow traces around, but this thing is confusing me. Additionally half the traces disappear under the RAM slots making it awkward. All I really need is the pinout, is it MC146818 compatible?
Chip is labeled:
M5818 A1
9240 TS2
A28595
Underside:
TAIWAN
T1067
ACER LABS
I'm not getting a CLK signal on the ISA bus. So I'm trying to follow traces around, but this thing is confusing me. Additionally half the traces disappear under the RAM slots making it awkward. All I really need is the pinout, is it MC146818 compatible?
Chip is labeled:
M5818 A1
9240 TS2
A28595
Underside:
TAIWAN
T1067
ACER LABS