diff options
author | Florian Jung <flo@windfisch.org> | 2015-11-29 00:30:43 +0100 |
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committer | Florian Jung <flo@windfisch.org> | 2015-11-29 00:30:43 +0100 |
commit | 84b980994934d54b3dad6dd2184830f4464b9933 (patch) | |
tree | 9e5eb6fb283e791ff50f85c6d97d28ccc7dca6b6 /usbdrv/usbdrvasm165.inc | |
parent | 1923a8c9121788804a4e307688b6c45993f58205 (diff) |
usb hello world \o/
Diffstat (limited to 'usbdrv/usbdrvasm165.inc')
-rw-r--r-- | usbdrv/usbdrvasm165.inc | 452 |
1 files changed, 0 insertions, 452 deletions
diff --git a/usbdrv/usbdrvasm165.inc b/usbdrv/usbdrvasm165.inc deleted file mode 100644 index ae91588..0000000 --- a/usbdrv/usbdrvasm165.inc +++ /dev/null @@ -1,452 +0,0 @@ -/* Name: usbdrvasm165.inc - * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers - * Author: Christian Starkjohann - * Creation Date: 2007-04-22 - * Tabsize: 4 - * Copyright: (c) 2007 by OBJECTIVE DEVELOPMENT Software GmbH - * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt) - */ - -/* Do not link this file! Link usbdrvasm.S instead, which includes the - * appropriate implementation! - */ - -/* -General Description: -This file is the 16.5 MHz version of the USB driver. It is intended for the -ATTiny45 and similar controllers running on 16.5 MHz internal RC oscillator. -This version contains a phase locked loop in the receiver routine to cope with -slight clock rate deviations of up to +/- 1%. - -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! -*/ - -;Software-receiver engine. Strict timing! Don't change unless you can preserve timing! -;interrupt response time: 4 cycles + insn running = 7 max if interrupts always enabled -;max allowable interrupt latency: 59 cycles -> max 52 cycles interrupt disable -;max stack usage: [ret(2), r0, SREG, YL, YH, shift, x1, x2, x3, x4, cnt] = 12 bytes -;nominal frequency: 16.5 MHz -> 11 cycles per bit -; 16.3125 MHz < F_CPU < 16.6875 MHz (+/- 1.1%) -; Numbers in brackets are clocks counted from center of last sync bit -; when instruction starts - - -USB_INTR_VECTOR: -;order of registers pushed: YL, SREG [sofError], r0, YH, shift, x1, x2, x3, x4, cnt - push YL ;[-23] push only what is necessary to sync with edge ASAP - in YL, SREG ;[-21] - push YL ;[-20] -;---------------------------------------------------------------------------- -; 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 -waitForK: -;The following code results in a sampling window of < 1/4 bit which meets the spec. - sbis USBIN, USBMINUS ;[-15] - rjmp foundK ;[-14] - sbis USBIN, USBMINUS - rjmp foundK - sbis USBIN, USBMINUS - rjmp foundK - sbis USBIN, USBMINUS - rjmp foundK - sbis USBIN, USBMINUS - rjmp foundK - sbis USBIN, USBMINUS - 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 -foundK: ;[-12] -;{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 - push r0 ;[-12] -; [---] ;[-11] - push YH ;[-10] -; [---] ;[-9] - lds YL, usbInputBufOffset;[-8] -; [---] ;[-7] - clr YH ;[-6] - subi YL, lo8(-(usbRxBuf));[-5] [rx loop init] - sbci YH, hi8(-(usbRxBuf));[-4] [rx loop init] - mov r0, x2 ;[-3] [rx loop init] - sbis USBIN, USBMINUS ;[-2] we want two bits K (sample 2 cycles too early) - rjmp haveTwoBitsK ;[-1] - pop YH ;[0] undo the pushes from before - pop r0 ;[2] - rjmp waitForK ;[4] this was not the end of sync, retry -; The entire loop from waitForK until rjmp waitForK above must not exceed two -; bit times (= 22 cycles). - -;---------------------------------------------------------------------------- -; push more registers and initialize values while we sample the first bits: -;---------------------------------------------------------------------------- -haveTwoBitsK: ;[1] - push shift ;[1] - push x1 ;[3] - push x2 ;[5] - push x3 ;[7] - ldi shift, 0xff ;[9] [rx loop init] - ori x3, 0xff ;[10] [rx loop init] == ser x3, clear zero flag - - in x1, USBIN ;[11] <-- sample bit 0 - bst x1, USBMINUS ;[12] - bld shift, 0 ;[13] - push x4 ;[14] == phase -; [---] ;[15] - push cnt ;[16] -; [---] ;[17] - ldi phase, 0 ;[18] [rx loop init] - ldi cnt, USB_BUFSIZE;[19] [rx loop init] - rjmp rxbit1 ;[20] -; [---] ;[21] - -;---------------------------------------------------------------------------- -; Receiver loop (numbers in brackets are cycles within byte after instr) -;---------------------------------------------------------------------------- -/* -byte oriented operations done during loop: -bit 0: store data -bit 1: SE0 check -bit 2: overflow check -bit 3: catch up -bit 4: rjmp to achieve conditional jump range -bit 5: PLL -bit 6: catch up -bit 7: jump, fixup bitstuff -; 87 [+ 2] cycles ------------------------------------------------------------------- -*/ -continueWithBit5: - in x2, USBIN ;[055] <-- bit 5 - eor r0, x2 ;[056] - or phase, r0 ;[057] - sbrc phase, USBMINUS ;[058] - lpm ;[059] optional nop3; modifies r0 - in phase, USBIN ;[060] <-- phase - eor x1, x2 ;[061] - bst x1, USBMINUS ;[062] - bld shift, 5 ;[063] - andi shift, 0x3f ;[064] - in x1, USBIN ;[065] <-- bit 6 - breq unstuff5 ;[066] *** unstuff escape - eor phase, x1 ;[067] - eor x2, x1 ;[068] - bst x2, USBMINUS ;[069] - bld shift, 6 ;[070] -didUnstuff6: ;[ ] - in r0, USBIN ;[071] <-- phase - cpi shift, 0x02 ;[072] - brlo unstuff6 ;[073] *** unstuff escape -didUnstuff5: ;[ ] - nop2 ;[074] -; [---] ;[075] - in x2, USBIN ;[076] <-- bit 7 - eor x1, x2 ;[077] - bst x1, USBMINUS ;[078] - bld shift, 7 ;[079] -didUnstuff7: ;[ ] - eor r0, x2 ;[080] - or phase, r0 ;[081] - in r0, USBIN ;[082] <-- phase - cpi shift, 0x04 ;[083] - brsh rxLoop ;[084] -; [---] ;[085] -unstuff7: ;[ ] - andi x3, ~0x80 ;[085] - ori shift, 0x80 ;[086] - in x2, USBIN ;[087] <-- sample stuffed bit 7 - nop ;[088] - rjmp didUnstuff7 ;[089] -; [---] ;[090] - ;[080] - -unstuff5: ;[067] - eor phase, x1 ;[068] - andi x3, ~0x20 ;[069] - ori shift, 0x20 ;[070] - in r0, USBIN ;[071] <-- phase - mov x2, x1 ;[072] - nop ;[073] - nop2 ;[074] -; [---] ;[075] - in x1, USBIN ;[076] <-- bit 6 - eor r0, x1 ;[077] - or phase, r0 ;[078] - eor x2, x1 ;[079] - bst x2, USBMINUS ;[080] - bld shift, 6 ;[081] no need to check bitstuffing, we just had one - in r0, USBIN ;[082] <-- phase - rjmp didUnstuff5 ;[083] -; [---] ;[084] - ;[074] - -unstuff6: ;[074] - andi x3, ~0x40 ;[075] - in x1, USBIN ;[076] <-- bit 6 again - ori shift, 0x40 ;[077] - nop2 ;[078] -; [---] ;[079] - rjmp didUnstuff6 ;[080] -; [---] ;[081] - ;[071] - -unstuff0: ;[013] - eor r0, x2 ;[014] - or phase, r0 ;[015] - andi x2, USBMASK ;[016] check for SE0 - in r0, USBIN ;[017] <-- phase - breq didUnstuff0 ;[018] direct jump to se0 would be too long - andi x3, ~0x01 ;[019] - ori shift, 0x01 ;[020] - mov x1, x2 ;[021] mov existing sample - in x2, USBIN ;[022] <-- bit 1 again - rjmp didUnstuff0 ;[023] -; [---] ;[024] - ;[014] - -unstuff1: ;[024] - eor r0, x1 ;[025] - or phase, r0 ;[026] - andi x3, ~0x02 ;[027] - in r0, USBIN ;[028] <-- phase - ori shift, 0x02 ;[029] - mov x2, x1 ;[030] - rjmp didUnstuff1 ;[031] -; [---] ;[032] - ;[022] - -unstuff2: ;[035] - eor r0, x2 ;[036] - or phase, r0 ;[037] - andi x3, ~0x04 ;[038] - in r0, USBIN ;[039] <-- phase - ori shift, 0x04 ;[040] - mov x1, x2 ;[041] - rjmp didUnstuff2 ;[042] -; [---] ;[043] - ;[033] - -unstuff3: ;[043] - in x2, USBIN ;[044] <-- bit 3 again - eor r0, x2 ;[045] - or phase, r0 ;[046] - andi x3, ~0x08 ;[047] - ori shift, 0x08 ;[048] - nop ;[049] - in r0, USBIN ;[050] <-- phase - rjmp didUnstuff3 ;[051] -; [---] ;[052] - ;[042] - -unstuff4: ;[053] - andi x3, ~0x10 ;[054] - in x1, USBIN ;[055] <-- bit 4 again - ori shift, 0x10 ;[056] - rjmp didUnstuff4 ;[057] -; [---] ;[058] - ;[048] - -rxLoop: ;[085] - eor x3, shift ;[086] reconstruct: x3 is 0 at bit locations we changed, 1 at others - in x1, USBIN ;[000] <-- bit 0 - st y+, x3 ;[001] -; [---] ;[002] - eor r0, x1 ;[003] - or phase, r0 ;[004] - eor x2, x1 ;[005] - in r0, USBIN ;[006] <-- phase - ser x3 ;[007] - bst x2, USBMINUS ;[008] - bld shift, 0 ;[009] - andi shift, 0xf9 ;[010] -rxbit1: ;[ ] - in x2, USBIN ;[011] <-- bit 1 - breq unstuff0 ;[012] *** unstuff escape - andi x2, USBMASK ;[013] SE0 check for bit 1 -didUnstuff0: ;[ ] Z only set if we detected SE0 in bitstuff - breq se0 ;[014] - eor r0, x2 ;[015] - or phase, r0 ;[016] - in r0, USBIN ;[017] <-- phase - eor x1, x2 ;[018] - bst x1, USBMINUS ;[019] - bld shift, 1 ;[020] - andi shift, 0xf3 ;[021] -didUnstuff1: ;[ ] - in x1, USBIN ;[022] <-- bit 2 - breq unstuff1 ;[023] *** unstuff escape - eor r0, x1 ;[024] - or phase, r0 ;[025] - subi cnt, 1 ;[026] overflow check - brcs overflow ;[027] - in r0, USBIN ;[028] <-- phase - eor x2, x1 ;[029] - bst x2, USBMINUS ;[030] - bld shift, 2 ;[031] - andi shift, 0xe7 ;[032] -didUnstuff2: ;[ ] - in x2, USBIN ;[033] <-- bit 3 - breq unstuff2 ;[034] *** unstuff escape - eor r0, x2 ;[035] - or phase, r0 ;[036] - eor x1, x2 ;[037] - bst x1, USBMINUS ;[038] - in r0, USBIN ;[039] <-- phase - bld shift, 3 ;[040] - andi shift, 0xcf ;[041] -didUnstuff3: ;[ ] - breq unstuff3 ;[042] *** unstuff escape - nop ;[043] - in x1, USBIN ;[044] <-- bit 4 - eor x2, x1 ;[045] - bst x2, USBMINUS ;[046] - bld shift, 4 ;[047] -didUnstuff4: ;[ ] - eor r0, x1 ;[048] - or phase, r0 ;[049] - in r0, USBIN ;[050] <-- phase - andi shift, 0x9f ;[051] - breq unstuff4 ;[052] *** unstuff escape - rjmp continueWithBit5;[053] -; [---] ;[054] - -macro POP_STANDARD ; 16 cycles - pop cnt - pop x4 - pop x3 - pop x2 - pop x1 - pop shift - pop YH - pop r0 - 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 - -bitstuff7: - eor x1, x4 ;[4] - ldi x2, 0 ;[5] - nop2 ;[6] C is zero (brcc) - rjmp didStuff7 ;[8] - -bitstuffN: - eor x1, x4 ;[5] - ldi x2, 0 ;[6] - lpm ;[7] 3 cycle NOP, modifies r0 - out USBOUT, x1 ;[10] <-- out - rjmp didStuffN ;[0] - -#define bitStatus x3 - -sendNakAndReti: - ldi cnt, USBPID_NAK ;[-19] - rjmp sendCntAndReti ;[-18] -sendAckAndReti: - ldi cnt, USBPID_ACK ;[-17] -sendCntAndReti: - mov r0, cnt ;[-16] - ldi YL, 0 ;[-15] R0 address is 0 - ldi YH, 0 ;[-14] - ldi cnt, 2 ;[-13] -; rjmp usbSendAndReti fallthrough - -;usbSend: -;pointer to data in 'Y' -;number of bytes in 'cnt' -- including sync byte [range 2 ... 12] -;uses: x1...x4, shift, cnt, Y -;Numbers in brackets are time since first bit of sync pattern is sent -usbSendAndReti: ; 12 cycles until SOP - in x2, USBDDR ;[-12] - ori x2, USBMASK ;[-11] - sbi USBOUT, USBMINUS;[-10] prepare idle state; D+ and D- must have been 0 (no pullups) - in x1, USBOUT ;[-8] port mirror for tx loop - out USBDDR, x2 ;[-7] <- acquire bus -; need not init x2 (bitstuff history) because sync starts with 0 - ldi x4, USBMASK ;[-6] exor mask - ldi shift, 0x80 ;[-5] sync byte is first byte sent - ldi bitStatus, 0xff ;[-4] init bit loop counter, works for up to 12 bytes -byteloop: -bitloop: - sbrs shift, 0 ;[8] [-3] - eor x1, x4 ;[9] [-2] - out USBOUT, x1 ;[10] [-1] <-- out - ror shift ;[0] - ror x2 ;[1] -didStuffN: - cpi x2, 0xfc ;[2] - brcc bitstuffN ;[3] - nop ;[4] - subi bitStatus, 37 ;[5] 256 / 7 ~=~ 37 - brcc bitloop ;[6] when we leave the loop, bitStatus has almost the initial value - sbrs shift, 0 ;[7] - eor x1, x4 ;[8] - ror shift ;[9] -didStuff7: - out USBOUT, x1 ;[10] <-- out - ror x2 ;[0] - cpi x2, 0xfc ;[1] - brcc bitstuff7 ;[2] - ld shift, y+ ;[3] - dec cnt ;[5] - brne byteloop ;[6] -;make SE0: - cbr x1, USBMASK ;[7] prepare SE0 [spec says EOP may be 21 to 25 cycles] - lds x2, usbNewDeviceAddr;[8] - lsl x2 ;[10] we compare with left shifted address - out USBOUT, x1 ;[11] <-- out SE0 -- from now 2 bits = 22 cycles until bus idle -;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 - subi YL, 2 ;[0] Only assign address on data packets, not ACK/NAK in r0 - sbci YH, 0 ;[1] - breq skipAddrAssign ;[2] - sts usbDeviceAddr, x2; if not skipped: SE0 is one cycle longer -skipAddrAssign: -;end of usbDeviceAddress transfer - ldi x2, 1<<USB_INTR_PENDING_BIT;[4] int0 occurred during TX -- clear pending flag - USB_STORE_PENDING(x2) ;[5] - ori x1, USBIDLE ;[6] - in x2, USBDDR ;[7] - cbr x2, USBMASK ;[8] set both pins to input - mov x3, x1 ;[9] - cbr x3, USBMASK ;[10] configure no pullup on both pins - ldi x4, 4 ;[11] -se0Delay: - dec x4 ;[12] [15] [18] [21] - brne se0Delay ;[13] [16] [19] [22] - out USBOUT, x1 ;[23] <-- out J (idle) -- end of SE0 (EOP signal) - out USBDDR, x2 ;[24] <-- release bus now - out USBOUT, x3 ;[25] <-- ensure no pull-up resistors are active - rjmp doReturn - |