added PS/2 to USB converter use V-USB as protocol stack

1 files changed, 453 insertions, 0 deletions

diff --git a/usbdrv/usbdrvasm165.inc b/usbdrv/usbdrvasm165.inc
new file mode 100644
index 000000000..79b3c61cf
--- /dev/null
+++ b/usbdrv/usbdrvasm165.inc
@@ -0,0 +1,453 @@
+/* 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
+