Cypress CY7C1256V18, CY7C1241V18 manual Write Cycle Descriptions, Comments, Remains unaltered

										CY7C1241V18, CY7C1256V18
										CY7C1243V18, CY7C1245V18
Write Cycle Descriptions
The write cycle description table for CY7C1241V18 and CY7C1243V18 follows.[2, 10]
	BWS	0/	BWS	1/	K					Comments
								K
	NWS0		NWS1
	L		L		L–H			–	During the data portion of a write sequence:
									CY7C1241V18 − both nibbles (D[7:0]) are written into the device.
									CY7C1243V18 − both bytes (D[17:0]) are written into the device.
	L		L		–		L-H		During the data portion of a write sequence:
									CY7C1241V18 − both nibbles (D[7:0]) are written into the device.
									CY7C1243V18 − both bytes (D[17:0]) are written into the device.
	L		H		L–H			–	During the data portion of a write sequence:
									CY7C1241V18 − only the lower nibble (D[3:0]) is written into the device, D[7:4]		remains unaltered.
									CY7C1243V18 − only the lower byte (D[8:0]) is written into the device, D[17:9]		remains unaltered.
	L		H		–		L–H		During the data portion of a write sequence:
									CY7C1241V18 − only the lower nibble (D[3:0]) is written into the device, D[7:4]		remains unaltered.
									CY7C1243V18 − only the lower byte (D[8:0]) is written into the device, D[17:9]		remains unaltered.
	H		L		L–H			–	During the data portion of a write sequence:
									CY7C1241V18 − only the upper nibble (D[7:4]) is written into the device, D[3:0]		remains unaltered.
									CY7C1243V18 − only the upper byte (D[17:9]) is written into the device, D[8:0]		remains unaltered.
	H		L		–		L–H		During the data portion of a write sequence:
									CY7C1241V18 − only the upper nibble (D[7:4]) is written into the device, D[3:0]		remains unaltered.
									CY7C1243V18 − only the upper byte (D[17:9]) is written into the device, D[8:0]		remains unaltered.
	H		H		L–H			–	No data is written into the devices during this portion of a write operation.
	H		H		–		L–H		No data is written into the devices during this portion of a write operation.
Write Cycle Descriptions
The write cycle description table for CY7C1256V18 follows.[2, 10]
	BWS	0	K			K				Comments
	L		L–H			–		During the data portion of a write sequence, the single byte (D[8:0]) is written into the device.
	L		–		L–H			During the data portion of a write sequence, the single byte (D[8:0]) is written into the device.
	H		L–H			–		No data is written into the device during this portion of a write operation.
	H		–		L–H			No data is written into the device during this portion of a write operation.

Note

10.Assumes a write cycle was initiated per the Write Cycle Description Table. NWS0, NWS1, BWS0, BWS1, BWS2, and BWS3 can be altered in different portions of a write cycle, as long as the setup and hold requirements are met.

Document Number: 001-06365 Rev. *D Page 11 of 28

[+] Feedback