Hi Dear Tsuneo
Excuse me if this code hasn't any comments
But it seems it is readable.Isn't it?

bLength                 EQU 30H
bDescriptorType         EQU 31H
bcdUSBH                 EQU 32H
bcdUSBL                 EQU 33H
bDeviceClass            EQU 34H
bDeviceSubclass         EQU 35H
bDeviceProtocol         EQU 36H
bMaxPacketSize          EQU 37H
idVendorH               EQU 38H
idVendorL               EQU 39H
idProductH              EQU 3AH
idProductL              EQU 3BH
bcdDeviceH              EQU 3CH
bcdDeviceL              EQU 3DH
iManufacture            EQU 3EH
iProducts               EQU 3FH
iSerialNumber           EQU 40H
bNumConfigurations      EQU 41H


wTotallLengthH          EQU 32H
wTotallLengthL          EQU 33H
bNumInterface           EQU 34H
bConfigurationValue     EQU 35H
iConfiguration          EQU 36H
bmAttributes            EQU 37H
MaxPower                EQU 38H

bInterfaceNumber        EQU 32H
bAlternateSettings      EQU 33H
bNumEndpoints           EQU 34H
bInterfaceClass         EQU 35H
bInterfaceSubclass      EQU 36H
bInterfaceProtocol      EQU 37H
iInterface              EQU 38H

bEndpointAddress        EQU 32H
bmAttributes1           EQU 33H
wMaxPacketSizeH         EQU 34H
wMaxPacketSizeL         EQU 35H
bInterval               EQU 36H

NUMBER_OF_FRAME         EQU 78H

WRITE_TO_BUFFER_DEVICE_DESCRIPTORS:
MOV bLength,#12H
MOV bDescriptorType,#01H
MOV bcdUSBL,#10H
MOV bcdUSBH,#01H
MOV bDeviceClass,#00H
MOV bDeviceSubclass,#00H
MOV bDeviceProtocol,#00H
MOV bMaxPacketSize,#8H
MOV idVendorH,#34H
MOV idVendorL,#12H
MOV idProductH,#01H
MOV idProductL,#00H
MOV bcdDeviceH,#00H
MOV bcdDeviceL,#01H
MOV iManufacture,#01H
MOV iProducts,#02H
MOV iSerialNumber,#03H
MOV bNumConfigurations,#01H
CALL WRITE_18_BYTE_DESCRIPTORS
RET

WRITE_18_BYTE_DESCRIPTORS:
CALL SELECT_CONTROL_IN_ENDPOINT
MOV A,NUMBER_OF_FRAME
INC NUMBER_OF_FRAME
CJNE A,#0,SECOND_8_BYTES
CALL WRITE_BUFFER
MOV DYTA,#8
CALL USB_DATA_WRITE
FIST_8_BYTE:
MOV R0,#30H
SAVING1:
MOV DYTA,@R0
CALL USB_DATA_WRITE
INC R0
MOV A,R0
CJNE A,#38H,SAVING1
RET

SECOND_8_BYTES:
CJNE A,#1,THIRD_2_BYTES
CALL WRITE_BUFFER
MOV DYTA,#8
CALL USB_DATA_WRITE
MOV R0,#38H
SAVING2:
MOV DYTA,@R0
CALL USB_DATA_WRITE
INC R0
MOV A,R0
CJNE A,#40H,SAVING2
RET

THIRD_2_BYTES:
MOV NUMBER_OF_FRAME,#0
CALL WRITE_BUFFER
MOV R0,#40H
MOV DYTA,#2
CALL USB_DATA_WRITE
SAVING3:
MOV DYTA,@R0
CALL USB_DATA_WRITE
INC R0
MOV A,R0
CJNE A,#42H,SAVING3
CALL SEND_ZERO_LENGTH_PACKET
RET