soufei
求讲解飞思卡尔908jb8汇编代码的意思,本人初学飞思卡尔汇编，下面是一段908jb8汇编代码，请高手讲解一下代码的思，谢谢！
FLASH:E190 sub_E190: ; CODE XREF: sub_E1AB↓P
FLASH:E190 ; __RESET_0+11↓P
FLASH:E190 6E 00 94 mov #0, byte_94 ；byte_94是一个8位内存地址
FLASH:E193 3F 95 clr byte_95 ；byte_95是一个8位内存地址
FLASH:E195 3F 96 clr byte_96 ； byte_96是一个8位内存地址
FLASH:E197 6E 80 38 mov #$80, UADDR ; USB Address Register
FLASH:E19A 3F 3B clr UCR0 ; USB Control Register 0
FLASH:E19C 3F 3C clr UCR1 ; USB Control Register 1
FLASH:E19E 3F 19 clr UCR2 ; USB Control Register 2
FLASH:E1A0 3F 1B clr UCR4 ; USB Control Register 4
FLASH:E1A2 3F 39 clr UIR0 ; USB Interrupt Register 0
FLASH:E1A4 6E FF 18 mov #$FF, UIR2 ; USB Interrupt Register 2
FLASH:E1A7 6E 44 1A mov #$44, UCR3 ; ‘D’ ; USB Control Register 3
FLASH:E1AA 81 rts
FLASH:E1AA ; End of function sub_E190
FLASH:E1AA
FLASH:E1AB
FLASH:E1AB ; =============== S U B R O U T I N E =======================================
FLASH:E1AB
FLASH:E1AB
FLASH:E1AB sub_E1AB: ; CODE XREF: USB_0+6↓P
FLASH:E1AB CD E1 90 jsr sub_E190
FLASH:E1AE 6E 03 39 mov #3, UIR0 ; USB Interrupt Register 0
FLASH:E1B1 6E 40 18 mov #$40, UIR2 ; ‘@’ ; USB Interrupt Register 2
FLASH:E1B4 6E 10 3B mov #$10, UCR0 ; USB Control Register 0
FLASH:E1B7 6E 80 38 mov #$80, UADDR ; USB Address Register
FLASH:E1BA 6E 01 94 mov #1, byte_94
FLASH:E1BD 81 rts
FLASH:E1BD ; End of function sub_E1AB
FLASH:E1BD
FLASH:E1BE
FLASH:E1BE ; =============== S U B R O U T I N E =======================================
FLASH:E1BE
FLASH:E1BE
FLASH:E1BE sub_E1BE: ; CODE XREF: __RESET_0+B↓P
FLASH:E1BE 6E 20 1D mov #$20, POCR ; ‘ ‘ ; Port Option Control Register
FLASH:E1C1 3F 00 clr PTA ; Port A Data Register
FLASH:E1C3 6E 00 04 mov #0, DDRA ; Data Direction Register A
FLASH:E1C6 3F 02 clr PTC ; Port C Data Register
FLASH:E1C8 3F 08 clr PTE ; Port E Data Register
FLASH:E1CA A6 FF lda #$FF
FLASH:E1CC B7 06 sta DDRC ; Data Direction Register C
FLASH:E1CE B7 09 sta DDRE ; Data Direction Register E
FLASH:E1D0 6E FC 03 mov #$FC, PTD ; Port D Data Register
FLASH:E1D3 6E FF 07 mov #$FF, DDRD ; Data Direction Register D
FLASH:E1D6 6E 88 9B mov #$88, byte_9B
FLASH:E1D9 81 rts
FLASH:E1D9 ; End of function sub_E1BE
FLASH:E1D9
