Update README.md

Author: lizwar

README.md

@@ -6,7 +6,7 @@ Gain the essential skills to build an embedded system using this practical 'lear
 
 ## [Download chapters 1-6 here](https://github.com/arm-university/A-Guide-to-Designing-Embedded-System-Applications-on-Arm-Cortex-M-Microcontrollers/blob/main/Beg.GuidetoDesigingEmbeddedSystems_ch1-6_textbook.pdf)
 
-## [Download chapters 7-12 here](https://github.com/arm-university/A-Guide-to-Designing-Embedded-System-Applications-on-Arm-Cortex-M-Microcontrollers/blob/main/ch7-12_Beg.%20Guide%20to%20Designing%20Embedded%20System%20Applications%20on%20Arm%20Cortex-M%20Microcontrollers.pdf)
+## [Download chapters 7-12 here](https://github.com/arm-university/A-Guide-to-Designing-Embedded-System-Applications-on-Arm-Cortex-M-Microcontrollers/blob/main/Beg.GuidetoDesigingEmbeddedSystems_ch7-12_textbook.pdf)
 
 ## About this Book
 This textbook is the perfect introduction for the beginner looking to enter the exciting world of embedded devices and IoT. Over the course of twelve chapters, readers will gain the practical skills needed to build a fully functional smart home device featuring a fire alarm, motion detector and security sensor.