Digi NS9215 manual Address A070 004C, Active to active command period tRC

M E M O R Y C O N T RO L L E R

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Dynamic Memory Active to Active Command Period register. .

D y n a m i c M e m o r y A c t i v e t o A c t i v e C o m m a n d P e r i o d r e g i s t e r

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Address: A070 0048

The Dynamic Memory Active to Active Command Period register allows you to program the active to active command period, tRC. It is recommended that this register be modified during system initialization, or when there are no current or outstanding transactions. Wait until the memory controller is idle, then enter low- power or disabled mode. This value normally is found in SDRAM datasheets as tRC.

Note: The Dynamic Memory Active to Active Command period register is used for all four dynamic memory chip selects. The worst case value for all chip selects must be programmed.

Register

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16
							Reserved
15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
					Reserved									RC

Register bit

assignment	Bits	Access	Mnemonic	Description
	D31:05	N/A	Reserved	N/A (do not modify)
	D04:00	R/W	RC	Active to active command period (tRC)
				0x0–0x1E
				n+1 clock cycles, where the delay is in clk_out cycles.

0x1F

32 clock cycles (reset value on reset_n)

D y n a m i c M e m o r y A u t o R e f r e s h P e r i o d r e g i s t e r

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Address: A070 004C

The Dynamic Memory Auto Refresh Period register allows you to program the auto- refresh period and the auto-refresh to active command period, tRFC. It is recommended that this register be modified during initialization, or when there are no current or outstanding transactions. Wait until the memory controller is idle, then enter low-power or disabled mode. This value normally is found in SDRAM datasheets as tRFC or tRC.

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