muflax
/
ergodox-firmware
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

(lib/eeprom: doc and makefile update)

partial-rewrite
Ben Blazak 2013-06-10 23:53:34 -07:00
parent be8c826e90
commit 30da4f3d31
3 changed files with 19 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
firmware/keyboard/ergodox/options.mk
View File

@ -34,6 +34,9 @@ KEYBOARD_LAYOUTS := \
CURDIRS := $(CURDIR) $(CURDIRS)
# -------
CURDIR := $(ROOTDIR)/lib/eeprom
include $(CURDIR)/options.mk
# -------
CURDIR := $(ROOTDIR)/lib/twi
include $(CURDIR)/options.mk
# -------

6
firmware/lib/eeprom.h
View File

@ -9,7 +9,11 @@
*
* Prefix: `eeprom__`
*
* Notes: TODO
* Notes:
* - This is meant to be a replacement for the read, write, and update
* functions provided by `<avr/eeprom.h>`, and should be preferred for those
* operations. There are other things provided by that header that may be
* useful however, and it's likely that both will be needed.
*/

18
firmware/lib/eeprom/atmega32u4.c
View File

@ -7,11 +7,6 @@
/** description
* Implements the EEPROM interface defined in "../eeprom.h" for the ATMega32U4
*
* This is meant to be a replacement for the read, write, and update functions
* provided by `<avr/eeprom.h>`, and should be preferred for those operations.
* There are other things provided by that header that may be useful however,
* and it's likely that both will be needed.
*
* These functions (and most of the comments) are taken more or less straight
* from the data sheet, section 5.3
*
@ -21,6 +16,11 @@
* - The address passed as `address` to any of the functions is valid.
* - A write to flash memory (PROGMEM) will never be in progress when any of
* these functions are called.
*
* Warnings:
* - These functions are *not* reentrant (i.e. they must never be called within
* an interrupt unless all calls to these functions are protected by having
* interrupts disabled for the duration of the call).
*/
@ -35,7 +35,9 @@
* Implementation notes:
*
* - If a write is in progress when this function is called, this function will
* busy wait until the write has been completed.
* busy wait until the write has been completed. This may take quite some
* time (up to 3.4 ms if a write has just been started), so you should be
* careful about when this function is called.
*/
uint8_t eeprom__read(uint8_t * address) {
while (EECR & (1<<EEPE)); // wait for previous write to complete
@ -48,7 +50,9 @@ uint8_t eeprom__read(uint8_t * address) {
* Implementation notes:
*
* - If another write is in progress when this function is called, this
* function will busy wait until the first write has been completed.
* function will busy wait until the first write has been completed. This
* may take quite some time (up to 3.4 ms if a write has just been started),
* so you should be careful about when this function is called.
*
* - This function starts the write to the EEPROM, but returns long before it
* has been completed.