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+# electronic shelf display
+## 2.9" version
+```
+ZBS 243 / SEM9110 8051 based core, 64kbyte flash, 8kbyte XRAM, 256 bytes iRAM 16 MHz, 802.15.4 2.4Ghz radio\
+2.9" e-paper display (BWR) 296x128 SSD1619 or UC8151\
+1Mbyte SPI flash\
+2x CR2540 button cell\
+Option: NXP NFC controller (I2C)
+```
+##  refs
+- https://openepaperlink.de/
+- https://github.com/jjwbruijn/OpenEPaperLink
+- https://github.com/atc1441/ZBS_Flasher
+- 
+## mass flash guide
+1.  backup 1kb eeprom
+2.  backup 64k flash 
+```
+python zbs_flasher mac write OpenEPaperLink/binaries/firmware.bin
+platformio run -e OpenEPaperLink_saola_AP
+platformio run -e OpenEPaperLink_saola_AP --target upload
+```
diff --git a/openepaperlink.md b/openepaperlink.md
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+++ b/openepaperlink.md
@@ -11,7 +11,7 @@
 
 ## minor additional
 
-- gpi max current for power
+- gpio max current for power
 - add espressif dev board 
 - simple power toggle
 - remote firmware update