Resetting LPC546xx while writing to external static RAM

取消
显示结果 
显示  仅  | 搜索替代 
您的意思是: 
已解决

Resetting LPC546xx while writing to external static RAM

跳至解决方案
982 次查看
vijo
Contributor III

Hi there,

ref. LPC546xx datasheet fig.25 External static memory read/write access

Does a low on the reset pin abort an external write cycle - if going low in the WR5 window - with a chance for leaving garbage in the addressed SRAM location?

Or will the reset action be delayed until the writecycle has finished?

Just short - is the action of a low reset asynchronous or synchronous with what the CPU is actually doing.

Best regards

Viggo

标签 (1)
标记 (1)
0 项奖励
回复
1 解答
881 次查看
xiangjun_rong
NXP TechSupport
NXP TechSupport

Hi, Viggo,

Yes, a reset event of the EMC module immediately aborts a memory write cycle to a external SRAM.

BR

Xiangjun Rong

在原帖中查看解决方案

0 项奖励
回复
3 回复数
881 次查看
xiangjun_rong
NXP TechSupport
NXP TechSupport

Hi, Viggo,

If you clear the EMCSYSCTRL[EMCRD] bit, both the POR RESET event and the Reset Pin/Watchdog Reset events can reset the EMC module.

If you set the EMCSYSCTRL[EMCRD] bit, only the POR RESET event can reset the EMC module, The Reset pin/Watchdog reset events can not reset the EMC module in the condition.

Once the EMC module is reset, all registers and functions of the EMC are initialized to it's Reset states immediately, in other words, the Reset event is asynchronous with the CPU action.


Have a great day,
TIC

-------------------------------------------------------------------------------
Note:
- If this post answers your question, please click the "Mark Correct" button. Thank you!

- We are following threads for 7 weeks after the last post, later replies are ignored
Please open a new thread and refer to the closed one, if you have a related question at a later point in time.
-------------------------------------------------------------------------------

0 项奖励
回复
881 次查看
vijo
Contributor III

thank you for the information TIC,

will a reset of the EMC module immediately abort a memory write cycle to a external SRAM ?

regards

Viggo

0 项奖励
回复
882 次查看
xiangjun_rong
NXP TechSupport
NXP TechSupport

Hi, Viggo,

Yes, a reset event of the EMC module immediately aborts a memory write cycle to a external SRAM.

BR

Xiangjun Rong

0 项奖励
回复