Memory Selection Jumpers JP3 JP10, U7 Device

Memory Selection Jumpers JP3 – JP10

The factory setting for the jumpers should be correct for the memory devices that came with your board. If you add or modify the type or size of memory, you must change the following jumpers accordingly. All jumpers are two-pin jumpers and are installed vertically.

U7 - ROM or EEPROM

FFFF

E000

JP8	JP9	JP10	U7 DEVICE
OFF	OFF	ON	8k EEPROM	< DEFAULT >
OFF	OFF	OFF	8k EPROM.
OFF	ON	OFF	32k EPROM.
ON	OFF	ON	32k EEPROM.

JP10 write protects U7 memory device when OFF.

U6 - RAM or EEPROM or ROM

DFFF

8000

U5 - RAM

7FFF

0100

JP4	JP5	JP7	JP6	U6 DEVICE
OFF	OFF	OFF	ON	8k RAM or EEPROM.
OFF	OFF	OFF	OFF	8k EPROM.
OFF	ON	ON	OFF	32k EPROM.
ON	OFF	ON	ON	32k RAM or EEPROM. < DEFAULT >
JP6 write protects U6 memory device when OFF.

For 32K device	JP3 = ON <DEFAULT> 32K bytes from 200 hex to 7FFF
	hex (minus register area, see memory map) and
	recommended position for Buffalo Monitor and Small C
	operation. No segmentation occurs.
For 8K device	JP3 = OFF 8K bytes from 0000 hex to 1FFF hex and
	mirrored at 2000 – 3FFF, 4000 – 5FFF, and 6000 - 7FFF.
	This position will allow CPU internal Ram and I/O ports to
	segment the 8K address space. Use this position to run
	Basic11 with an 8K device.

You can determine the size of memory devices by reading the label on top of the chip. Memory devices that contain 64 in the part number are usually 8K. Those with 256 are usually 32K.

The type of memory can also be determined by reading the chip label. If you don’t recognize the memory type you can look up the part number in a catalog or device manual. If the chip is by Atmel™ or XICOR™ it is probably an EEPROM. If it has HY or SEC it is probably RAM.

Memory Selection Jumpers JP3 – JP10

U7 DEVICE

JP4

JP5

JP7

JP6

U6 DEVICE