Mercurial > hg > Members > kono > nitros9-code
view level1/modules/dwrdmess.asm @ 2668:07441dfebc27 lwtools-port
Make tocgen build with lwasm
lwasm does not treat a trailing colon as part of the symbol name. Removed
trailing colons on symbol references.
| author | William Astle <lost@l-w.ca> |
|---|---|
| date | Sun, 10 Jun 2012 13:35:44 -0600 |
| parents | c92a6c65bbd9 |
| children | c505ae3120c4 |
line wrap: on
line source
******************************************************* * * DWRdMess * Receive a response from the DriveWire server via MESS FIFO * 4/27/10 AAW - Based on John Linville's example driver * * Entry: * X = starting address where data is to be stored * Y = number of bytes expected * * Exit: * CC = carry set on framing error, Z set if all bytes received * X = starting address of data received * Y = checksum * U is preserved. All accumulators are clobbered * DWRead clra ; clear Carry (no framing error) pshs u,x,cc ; preserve registers, push timeout msb orcc #$50 ; mask interrupts leau ,x ; U = storage ptr ldx #0 ; initialize checksum * Read a byte rxByte ldb $ffe1 ; check for data in FIFO beq rxByte ; loop while empty ldb $ffe0 ; read data value stb ,u+ ; store received byte to memory abx ; update checksum leay ,-y ; decrement request count bne rxByte ; loop if another byte wanted * Clean up, set status and return rxExit leay ,x ; return checksum in Y puls cc,x,u,pc ; restore registers and return setdp $00