mirror of
https://github.com/Keychron/qmk_firmware.git
synced 2024-12-30 21:38:01 +06:00
454 lines
17 KiB
PHP
454 lines
17 KiB
PHP
/* 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)
|
|
* Revision: $Id: usbdrvasm165.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 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
|
|
|