diff options
Diffstat (limited to 'usbdrv/usbdrvasm15.inc')
-rw-r--r-- | usbdrv/usbdrvasm15.inc | 423 |
1 files changed, 0 insertions, 423 deletions
diff --git a/usbdrv/usbdrvasm15.inc b/usbdrv/usbdrvasm15.inc deleted file mode 100644 index 401b7f8fff..0000000000 --- a/usbdrv/usbdrvasm15.inc +++ /dev/null @@ -1,423 +0,0 @@ -/* Name: usbdrvasm15.inc - * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers - * Author: contributed by V. Bosch - * Creation Date: 2007-08-06 - * Tabsize: 4 - * Copyright: (c) 2007 by OBJECTIVE DEVELOPMENT Software GmbH - * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt) - * Revision: $Id: usbdrvasm15.inc 740 2009-04-13 18:23:31Z cs $ - */ - -/* Do not link this file! Link usbdrvasm.S instead, which includes the - * appropriate implementation! - */ - -/* -General Description: -This file is the 15 MHz version of the asssembler part of the USB driver. It -requires a 15 MHz crystal (not a ceramic resonator and not a calibrated RC -oscillator). - -See usbdrv.h for a description of the entire driver. - -Since almost all of this code is timing critical, don't change unless you -really know what you are doing! Many parts require not only a maximum number -of CPU cycles, but even an exact number of cycles! -*/ - -;max stack usage: [ret(2), YL, SREG, YH, bitcnt, shift, x1, x2, x3, x4, cnt] = 12 bytes -;nominal frequency: 15 MHz -> 10.0 cycles per bit, 80.0 cycles per byte -; Numbers in brackets are clocks counted from center of last sync bit -; when instruction starts - -;---------------------------------------------------------------------------- -; order of registers pushed: -; YL, SREG [sofError] YH, shift, x1, x2, x3, bitcnt, cnt, x4 -;---------------------------------------------------------------------------- -USB_INTR_VECTOR: - push YL ;2 push only what is necessary to sync with edge ASAP - in YL, SREG ;1 - push YL ;2 -;---------------------------------------------------------------------------- -; Synchronize with sync pattern: -; -; sync byte (D-) pattern LSb to MSb: 01010100 [1 = idle = J, 0 = K] -; sync up with J to K edge during sync pattern -- use fastest possible loops -;The first part waits at most 1 bit long since we must be in sync pattern. -;YL is guarenteed to be < 0x80 because I flag is clear. When we jump to -;waitForJ, ensure that this prerequisite is met. -waitForJ: - inc YL - sbis USBIN, USBMINUS - brne waitForJ ; just make sure we have ANY timeout -;------------------------------------------------------------------------------- -; The following code results in a sampling window of < 1/4 bit -; which meets the spec. -;------------------------------------------------------------------------------- -waitForK: ;- - sbis USBIN, USBMINUS ;1 [00] <-- sample - rjmp foundK ;2 [01] - sbis USBIN, USBMINUS ; <-- sample - rjmp foundK - sbis USBIN, USBMINUS ; <-- sample - rjmp foundK - sbis USBIN, USBMINUS ; <-- sample - rjmp foundK - sbis USBIN, USBMINUS ; <-- sample - rjmp foundK - sbis USBIN, USBMINUS ; <-- sample - rjmp foundK -#if USB_COUNT_SOF - lds YL, usbSofCount - inc YL - sts usbSofCount, YL -#endif /* USB_COUNT_SOF */ -#ifdef USB_SOF_HOOK - USB_SOF_HOOK -#endif - rjmp sofError -;------------------------------------------------------------------------------ -; {3, 5} after falling D- edge, average delay: 4 cycles [we want 5 for -; center sampling] -; we have 1 bit time for setup purposes, then sample again. -; Numbers in brackets are cycles from center of first sync (double K) -; bit after the instruction -;------------------------------------------------------------------------------ -foundK: ;- [02] - lds YL, usbInputBufOffset;2 [03+04] tx loop - push YH ;2 [05+06] - clr YH ;1 [07] - subi YL, lo8(-(usbRxBuf)) ;1 [08] [rx loop init] - sbci YH, hi8(-(usbRxBuf)) ;1 [09] [rx loop init] - push shift ;2 [10+11] - ser shift ;1 [12] - sbis USBIN, USBMINUS ;1 [-1] [13] <--sample:we want two bits K (sample 1 cycle too early) - rjmp haveTwoBitsK ;2 [00] [14] - pop shift ;2 [15+16] undo the push from before - pop YH ;2 [17+18] undo the push from before - rjmp waitForK ;2 [19+20] this was not the end of sync, retry -; The entire loop from waitForK until rjmp waitForK above must not exceed two -; bit times (= 20 cycles). - -;---------------------------------------------------------------------------- -; push more registers and initialize values while we sample the first bits: -;---------------------------------------------------------------------------- -haveTwoBitsK: ;- [01] - push x1 ;2 [02+03] - push x2 ;2 [04+05] - push x3 ;2 [06+07] - push bitcnt ;2 [08+09] - in x1, USBIN ;1 [00] [10] <-- sample bit 0 - bst x1, USBMINUS ;1 [01] - bld shift, 0 ;1 [02] - push cnt ;2 [03+04] - ldi cnt, USB_BUFSIZE ;1 [05] - push x4 ;2 [06+07] tx loop - rjmp rxLoop ;2 [08] -;---------------------------------------------------------------------------- -; Receiver loop (numbers in brackets are cycles within byte after instr) -;---------------------------------------------------------------------------- -unstuff0: ;- [07] (branch taken) - andi x3, ~0x01 ;1 [08] - mov x1, x2 ;1 [09] x2 contains last sampled (stuffed) bit - in x2, USBIN ;1 [00] [10] <-- sample bit 1 again - andi x2, USBMASK ;1 [01] - breq se0Hop ;1 [02] SE0 check for bit 1 - ori shift, 0x01 ;1 [03] 0b00000001 - nop ;1 [04] - rjmp didUnstuff0 ;2 [05] -;----------------------------------------------------- -unstuff1: ;- [05] (branch taken) - mov x2, x1 ;1 [06] x1 contains last sampled (stuffed) bit - andi x3, ~0x02 ;1 [07] - ori shift, 0x02 ;1 [08] 0b00000010 - nop ;1 [09] - in x1, USBIN ;1 [00] [10] <-- sample bit 2 again - andi x1, USBMASK ;1 [01] - breq se0Hop ;1 [02] SE0 check for bit 2 - rjmp didUnstuff1 ;2 [03] -;----------------------------------------------------- -unstuff2: ;- [05] (branch taken) - andi x3, ~0x04 ;1 [06] - ori shift, 0x04 ;1 [07] 0b00000100 - mov x1, x2 ;1 [08] x2 contains last sampled (stuffed) bit - nop ;1 [09] - in x2, USBIN ;1 [00] [10] <-- sample bit 3 - andi x2, USBMASK ;1 [01] - breq se0Hop ;1 [02] SE0 check for bit 3 - rjmp didUnstuff2 ;2 [03] -;----------------------------------------------------- -unstuff3: ;- [00] [10] (branch taken) - in x2, USBIN ;1 [01] [11] <-- sample stuffed bit 3 one cycle too late - andi x2, USBMASK ;1 [02] - breq se0Hop ;1 [03] SE0 check for stuffed bit 3 - andi x3, ~0x08 ;1 [04] - ori shift, 0x08 ;1 [05] 0b00001000 - rjmp didUnstuff3 ;2 [06] -;---------------------------------------------------------------------------- -; extra jobs done during bit interval: -; -; bit 0: store, clear [SE0 is unreliable here due to bit dribbling in hubs], -; overflow check, jump to the head of rxLoop -; bit 1: SE0 check -; bit 2: SE0 check, recovery from delay [bit 0 tasks took too long] -; bit 3: SE0 check, recovery from delay [bit 0 tasks took too long] -; bit 4: SE0 check, none -; bit 5: SE0 check, none -; bit 6: SE0 check, none -; bit 7: SE0 check, reconstruct: x3 is 0 at bit locations we changed, 1 at others -;---------------------------------------------------------------------------- -rxLoop: ;- [09] - in x2, USBIN ;1 [00] [10] <-- sample bit 1 (or possibly bit 0 stuffed) - andi x2, USBMASK ;1 [01] - brne SkipSe0Hop ;1 [02] -se0Hop: ;- [02] - rjmp se0 ;2 [03] SE0 check for bit 1 -SkipSe0Hop: ;- [03] - ser x3 ;1 [04] - andi shift, 0xf9 ;1 [05] 0b11111001 - breq unstuff0 ;1 [06] -didUnstuff0: ;- [06] - eor x1, x2 ;1 [07] - bst x1, USBMINUS ;1 [08] - bld shift, 1 ;1 [09] - in x1, USBIN ;1 [00] [10] <-- sample bit 2 (or possibly bit 1 stuffed) - andi x1, USBMASK ;1 [01] - breq se0Hop ;1 [02] SE0 check for bit 2 - andi shift, 0xf3 ;1 [03] 0b11110011 - breq unstuff1 ;1 [04] do remaining work for bit 1 -didUnstuff1: ;- [04] - eor x2, x1 ;1 [05] - bst x2, USBMINUS ;1 [06] - bld shift, 2 ;1 [07] - nop2 ;2 [08+09] - in x2, USBIN ;1 [00] [10] <-- sample bit 3 (or possibly bit 2 stuffed) - andi x2, USBMASK ;1 [01] - breq se0Hop ;1 [02] SE0 check for bit 3 - andi shift, 0xe7 ;1 [03] 0b11100111 - breq unstuff2 ;1 [04] -didUnstuff2: ;- [04] - eor x1, x2 ;1 [05] - bst x1, USBMINUS ;1 [06] - bld shift, 3 ;1 [07] -didUnstuff3: ;- [07] - andi shift, 0xcf ;1 [08] 0b11001111 - breq unstuff3 ;1 [09] - in x1, USBIN ;1 [00] [10] <-- sample bit 4 - andi x1, USBMASK ;1 [01] - breq se0Hop ;1 [02] SE0 check for bit 4 - eor x2, x1 ;1 [03] - bst x2, USBMINUS ;1 [04] - bld shift, 4 ;1 [05] -didUnstuff4: ;- [05] - andi shift, 0x9f ;1 [06] 0b10011111 - breq unstuff4 ;1 [07] - nop2 ;2 [08+09] - in x2, USBIN ;1 [00] [10] <-- sample bit 5 - andi x2, USBMASK ;1 [01] - breq se0 ;1 [02] SE0 check for bit 5 - eor x1, x2 ;1 [03] - bst x1, USBMINUS ;1 [04] - bld shift, 5 ;1 [05] -didUnstuff5: ;- [05] - andi shift, 0x3f ;1 [06] 0b00111111 - breq unstuff5 ;1 [07] - nop2 ;2 [08+09] - in x1, USBIN ;1 [00] [10] <-- sample bit 6 - andi x1, USBMASK ;1 [01] - breq se0 ;1 [02] SE0 check for bit 6 - eor x2, x1 ;1 [03] - bst x2, USBMINUS ;1 [04] - bld shift, 6 ;1 [05] -didUnstuff6: ;- [05] - cpi shift, 0x02 ;1 [06] 0b00000010 - brlo unstuff6 ;1 [07] - nop2 ;2 [08+09] - in x2, USBIN ;1 [00] [10] <-- sample bit 7 - andi x2, USBMASK ;1 [01] - breq se0 ;1 [02] SE0 check for bit 7 - eor x1, x2 ;1 [03] - bst x1, USBMINUS ;1 [04] - bld shift, 7 ;1 [05] -didUnstuff7: ;- [05] - cpi shift, 0x04 ;1 [06] 0b00000100 - brlo unstuff7 ;1 [07] - eor x3, shift ;1 [08] reconstruct: x3 is 0 at bit locations we changed, 1 at others - nop ;1 [09] - in x1, USBIN ;1 [00] [10] <-- sample bit 0 - st y+, x3 ;2 [01+02] store data - eor x2, x1 ;1 [03] - bst x2, USBMINUS ;1 [04] - bld shift, 0 ;1 [05] - subi cnt, 1 ;1 [06] - brcs overflow ;1 [07] - rjmp rxLoop ;2 [08] -;----------------------------------------------------- -unstuff4: ;- [08] - andi x3, ~0x10 ;1 [09] - in x1, USBIN ;1 [00] [10] <-- sample stuffed bit 4 - andi x1, USBMASK ;1 [01] - breq se0 ;1 [02] SE0 check for stuffed bit 4 - ori shift, 0x10 ;1 [03] - rjmp didUnstuff4 ;2 [04] -;----------------------------------------------------- -unstuff5: ;- [08] - ori shift, 0x20 ;1 [09] - in x2, USBIN ;1 [00] [10] <-- sample stuffed bit 5 - andi x2, USBMASK ;1 [01] - breq se0 ;1 [02] SE0 check for stuffed bit 5 - andi x3, ~0x20 ;1 [03] - rjmp didUnstuff5 ;2 [04] -;----------------------------------------------------- -unstuff6: ;- [08] - andi x3, ~0x40 ;1 [09] - in x1, USBIN ;1 [00] [10] <-- sample stuffed bit 6 - andi x1, USBMASK ;1 [01] - breq se0 ;1 [02] SE0 check for stuffed bit 6 - ori shift, 0x40 ;1 [03] - rjmp didUnstuff6 ;2 [04] -;----------------------------------------------------- -unstuff7: ;- [08] - andi x3, ~0x80 ;1 [09] - in x2, USBIN ;1 [00] [10] <-- sample stuffed bit 7 - andi x2, USBMASK ;1 [01] - breq se0 ;1 [02] SE0 check for stuffed bit 7 - ori shift, 0x80 ;1 [03] - rjmp didUnstuff7 ;2 [04] - -macro POP_STANDARD ; 16 cycles - pop x4 - pop cnt - pop bitcnt - pop x3 - pop x2 - pop x1 - pop shift - pop YH - endm -macro POP_RETI ; 5 cycles - pop YL - out SREG, YL - pop YL - endm - -#include "asmcommon.inc" - -;--------------------------------------------------------------------------- -; USB spec says: -; idle = J -; J = (D+ = 0), (D- = 1) -; K = (D+ = 1), (D- = 0) -; Spec allows 7.5 bit times from EOP to SOP for replies -;--------------------------------------------------------------------------- -bitstuffN: ;- [04] - eor x1, x4 ;1 [05] - clr x2 ;1 [06] - nop ;1 [07] - rjmp didStuffN ;1 [08] -;--------------------------------------------------------------------------- -bitstuff6: ;- [04] - eor x1, x4 ;1 [05] - clr x2 ;1 [06] - rjmp didStuff6 ;1 [07] -;--------------------------------------------------------------------------- -bitstuff7: ;- [02] - eor x1, x4 ;1 [03] - clr x2 ;1 [06] - nop ;1 [05] - rjmp didStuff7 ;1 [06] -;--------------------------------------------------------------------------- -sendNakAndReti: ;- [-19] - ldi x3, USBPID_NAK ;1 [-18] - rjmp sendX3AndReti ;1 [-17] -;--------------------------------------------------------------------------- -sendAckAndReti: ;- [-17] - ldi cnt, USBPID_ACK ;1 [-16] -sendCntAndReti: ;- [-16] - mov x3, cnt ;1 [-15] -sendX3AndReti: ;- [-15] - ldi YL, 20 ;1 [-14] x3==r20 address is 20 - ldi YH, 0 ;1 [-13] - ldi cnt, 2 ;1 [-12] -; rjmp usbSendAndReti fallthrough -;--------------------------------------------------------------------------- -;usbSend: -;pointer to data in 'Y' -;number of bytes in 'cnt' -- including sync byte [range 2 ... 12] -;uses: x1...x4, btcnt, shift, cnt, Y -;Numbers in brackets are time since first bit of sync pattern is sent -;We need not to match the transfer rate exactly because the spec demands -;only 1.5% precision anyway. -usbSendAndReti: ;- [-13] 13 cycles until SOP - in x2, USBDDR ;1 [-12] - ori x2, USBMASK ;1 [-11] - sbi USBOUT, USBMINUS ;2 [-09-10] prepare idle state; D+ and D- must have been 0 (no pullups) - in x1, USBOUT ;1 [-08] port mirror for tx loop - out USBDDR, x2 ;1 [-07] <- acquire bus - ; need not init x2 (bitstuff history) because sync starts with 0 - ldi x4, USBMASK ;1 [-06] exor mask - ldi shift, 0x80 ;1 [-05] sync byte is first byte sent - ldi bitcnt, 6 ;1 [-04] -txBitLoop: ;- [-04] [06] - sbrs shift, 0 ;1 [-03] [07] - eor x1, x4 ;1 [-02] [08] - ror shift ;1 [-01] [09] -didStuffN: ;- [09] - out USBOUT, x1 ;1 [00] [10] <-- out N - ror x2 ;1 [01] - cpi x2, 0xfc ;1 [02] - brcc bitstuffN ;1 [03] - dec bitcnt ;1 [04] - brne txBitLoop ;1 [05] - sbrs shift, 0 ;1 [06] - eor x1, x4 ;1 [07] - ror shift ;1 [08] -didStuff6: ;- [08] - nop ;1 [09] - out USBOUT, x1 ;1 [00] [10] <-- out 6 - ror x2 ;1 [01] - cpi x2, 0xfc ;1 [02] - brcc bitstuff6 ;1 [03] - sbrs shift, 0 ;1 [04] - eor x1, x4 ;1 [05] - ror shift ;1 [06] - ror x2 ;1 [07] -didStuff7: ;- [07] - ldi bitcnt, 6 ;1 [08] - cpi x2, 0xfc ;1 [09] - out USBOUT, x1 ;1 [00] [10] <-- out 7 - brcc bitstuff7 ;1 [01] - ld shift, y+ ;2 [02+03] - dec cnt ;1 [04] - brne txBitLoop ;1 [05] -makeSE0: - cbr x1, USBMASK ;1 [06] prepare SE0 [spec says EOP may be 19 to 23 cycles] - lds x2, usbNewDeviceAddr;2 [07+08] - lsl x2 ;1 [09] we compare with left shifted address -;2006-03-06: moved transfer of new address to usbDeviceAddr from C-Code to asm: -;set address only after data packet was sent, not after handshake - out USBOUT, x1 ;1 [00] [10] <-- out SE0-- from now 2 bits==20 cycl. until bus idle - subi YL, 20 + 2 ;1 [01] Only assign address on data packets, not ACK/NAK in x3 - sbci YH, 0 ;1 [02] - breq skipAddrAssign ;1 [03] - sts usbDeviceAddr, x2 ;2 [04+05] if not skipped: SE0 is one cycle longer -;---------------------------------------------------------------------------- -;end of usbDeviceAddress transfer -skipAddrAssign: ;- [03/04] - ldi x2, 1<<USB_INTR_PENDING_BIT ;1 [05] int0 occurred during TX -- clear pending flag - USB_STORE_PENDING(x2) ;1 [06] - ori x1, USBIDLE ;1 [07] - in x2, USBDDR ;1 [08] - cbr x2, USBMASK ;1 [09] set both pins to input - mov x3, x1 ;1 [10] - cbr x3, USBMASK ;1 [11] configure no pullup on both pins - ldi x4, 3 ;1 [12] -se0Delay: ;- [12] [15] - dec x4 ;1 [13] [16] - brne se0Delay ;1 [14] [17] - nop2 ;2 [18+19] - out USBOUT, x1 ;1 [20] <--out J (idle) -- end of SE0 (EOP sig.) - out USBDDR, x2 ;1 [21] <--release bus now - out USBOUT, x3 ;1 [22] <--ensure no pull-up resistors are active - rjmp doReturn ;1 [23] -;--------------------------------------------------------------------------- |