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author | cpldcpu <cpldcpu@gmail.com> | 2014-01-05 12:09:34 +0100 |
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committer | cpldcpu <cpldcpu@gmail.com> | 2014-01-05 12:09:34 +0100 |
commit | a1a11ed4888bfd84f2215321489b25944404b6ab (patch) | |
tree | 0ff67bd7f5f96267e103c38fc24b11cee4364f8b /firmware/main.c | |
parent | c4907c6896943eb3ff778cb007a9891ac7b68248 (diff) | |
download | micronucleus-a1a11ed4888bfd84f2215321489b25944404b6ab.tar.gz micronucleus-a1a11ed4888bfd84f2215321489b25944404b6ab.tar.bz2 micronucleus-a1a11ed4888bfd84f2215321489b25944404b6ab.zip |
firmware: first working version with polled usb
Diffstat (limited to 'firmware/main.c')
-rw-r--r-- | firmware/main.c | 64 |
1 files changed, 58 insertions, 6 deletions
diff --git a/firmware/main.c b/firmware/main.c index 1fdda03..a09bb4c 100644 --- a/firmware/main.c +++ b/firmware/main.c @@ -125,19 +125,21 @@ static void writeWordToPageBuffer(uint16_t data) { vectorTemp[0] = data; data = 0xC000 + (BOOTLOADER_ADDRESS/2) - 1; } - +/* if (currentAddress.w == USBPLUS_VECTOR_OFFSET * 2) { vectorTemp[1] = data; data = 0xC000 + (BOOTLOADER_ADDRESS/2) - 1; } - + */ // at end of page just before bootloader, write in tinyVector table // see http://embedded-creations.com/projects/attiny85-usb-bootloader-overview/avr-jtag-programmer/ // for info on how the tiny vector table works if (currentAddress.w == BOOTLOADER_ADDRESS - TINYVECTOR_RESET_OFFSET) { data = vectorTemp[0] + ((FLASHEND + 1) - BOOTLOADER_ADDRESS)/2 + 2 + RESET_VECTOR_OFFSET; +/* } else if (currentAddress.w == BOOTLOADER_ADDRESS - TINYVECTOR_USBPLUS_OFFSET) { data = vectorTemp[1] + ((FLASHEND + 1) - BOOTLOADER_ADDRESS)/2 + 1 + USBPLUS_VECTOR_OFFSET; +*/ #if (!OSCCAL_RESTORE) && OSCCAL_16_5MHz } else if (currentAddress.w == BOOTLOADER_ADDRESS - TINYVECTOR_OSCCAL_OFFSET) { data = OSCCAL; @@ -286,7 +288,7 @@ static void wait_usb_interrupt( void ) USB_INTR_VECTOR(); // Wait a little while longer in case another one comes - uchar n = 250; // about 90us timeout + uchar n = 50; // about 90us timeout do { if ( !--n ) goto handled; @@ -302,6 +304,8 @@ int main(void) { bootLoaderInit(); + DDRB|=3; + if (bootLoaderStartCondition()||(pgm_read_byte(BOOTLOADER_ADDRESS - TINYVECTOR_RESET_OFFSET + 1)==0xff)) { initHardware(); @@ -314,7 +318,9 @@ int main(void) { } do { - +// USB_INTR_PENDING = 1<<USB_INTR_PENDING_BIT; // <-- + +/* uint8_t n=200; while (--n) { @@ -323,12 +329,58 @@ int main(void) { // Vector interrupt manually USB_INTR_PENDING = 1<<USB_INTR_PENDING_BIT; USB_INTR_VECTOR(); - n=100; + n=50; // 25µs } } + */ + + + while ( !(USB_INTR_PENDING & (1<<USB_INTR_PENDING_BIT)) ); + USB_INTR_VECTOR(); + + command=cmd_local_nop; + PORTB|=_BV(PB1); + USB_INTR_PENDING = 1<<USB_INTR_PENDING_BIT; usbPoll(); - + + // Test whether another interrupt occured during the processing of USBpoll. + // If yes, we missed a data packet on the bus. This is not a big issue, since + // USB seems to allow timeout of up the two packets. (On my machine an USB + // error is triggers after the third missed packet.) + // The most critical situation occurs when a PID IN packet is missed due to + // it's short length. Each packet + timeout takes around 45µs, meaning that + // usbpoll must take less than 90µs or resyncing is not possible. + // To avoid synchronizing of the interrupt routine, we must not call it while + // a packet is transmitted. Therefore we have to wait until the bus is idle again. + // + // Just waiting for EOP (SE0) or no activity for 6 bus cycles is not enough, + // as the host may have been sending a multi-packet transmisstion (eg. OUT, DATA0/1) + // Restarting at the DATA packet may lead to errors. + // + // A safer way is to wait until the bus was idle for the the host-timeout + // period (18 bit times = 12µs). + + if (USB_INTR_PENDING & (1<<USB_INTR_PENDING_BIT)) // Usbpoll intersected with data packe + { + PORTB|=_BV(PB0); + uint8_t tx; + uint8_t timeout=(uint8_t)(10.0f*(F_CPU/1.0e6f)/7.0f+0.5); + tx=timeout; + + // loop takes 9 cycles + while (--tx) { + uint8_t usbin=USBIN; + + if (usbin&(1<<USB_CFG_DPLUS_BIT)) {tx=timeout;} + // if (!(usbin&USBMASK)) {t=2;} + + } + USB_INTR_PENDING = 1<<USB_INTR_PENDING_BIT; + PORTB&=~_BV(PB0); + } + PORTB&=~_BV(PB1); + if ( command != cmd_local_nop) { // Make sure all USB activity has finished before running any blocking events |